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The final conflict

Chaos has erupted throughout the known galaxy, threatening countless colonies and orbital habitats--as the Associative struggles vainly to keep the peace. Extreme measures are called for in these times of dire crisis, and the Star Marines are awakened from their voluntary 850-year cybe-hibe sleep. But General Trevor Garroway and his warriors are about to discover that the old rules of engagement have drastically changed . . .

The end begins with an old-style assault on rebels at the Tarantula Stargate. But true terror looms at the edges of known reality. Humankind's eternal enemy--the brutal, unstoppable Xul--approaches, wielding a weapon monstrous beyond imagining. Suddenly not only is the future in jeopardy, but the past is as well--and if the Marines fail to eliminate their relentless xenophobic foe once and for all, the Great Annihilator will obliterate every last trace of human existence.

400 pages, ebook

First published May 22, 2009

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345 people want to read

About the author

Ian Douglas

99 books571 followers
Ian Douglas is a pseudonym used by William H. Keith Jr..

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5 stars
288 (28%)
4 stars
386 (38%)
3 stars
253 (25%)
2 stars
65 (6%)
1 star
11 (1%)
Displaying 1 - 23 of 23 reviews
Profile Image for Dirk Grobbelaar.
843 reviews1,227 followers
September 3, 2024
In his opinion, Humankind could no more give up war than he could give up the ability to think.

This concludes both the Inheritance Trilogy and the Marines in Space series.

There is a case to be made that this is a somewhat odd entry in the series. It takes place more than 800 years after Galactic Corps, in which the Xul threat was apparently conclusively dealt with, so it does occasionally come across as a bit of a footnote to everything else that went before.

Nevertheless, I enjoyed it. There is a lot of exotic new tech on display here, and the differences between the “old” and “new” Marine corps makes for interesting dynamics.

“Even so, the astrophysicists are calling it a microquasar. It won’t scour the Galaxy of life, fortunately, but they estimate the total light output from our Galaxy will more than quintuple, and probably set the astronomers in Andromeda to scratching whatever they use for heads.”

Again, expect some big drama and even bigger explosions. I am also currently reading the Star Carrier series, so drawing comparisons is inevitable. Notably: the difference between the Xul and the Sh’daar, and the way that Artificial Intelligence is portrayed.

Similar in tone, but some different concepts. The one thing that stood out for me in this specific series (Marines in Space), is the mythos that the author has created around extra-terrestrial life and how it has affected humanity over the ages (such as being worshipped as gods and being responsible for key events in human history and evolution – without revealing spoilers).

In fact, Earth’s sun was so intrinsically faint as to be invisible to the naked eye at a distance of only thirty or forty light years, and he was looking for it across a gulf two thousand times greater than that. Each and every one of the stars he could see was brighter by far than Sol, and for every star he could see there were tens of thousands that he could not.
Earth’s sun, and its worlds, was lost within that unimaginable immensity.


The story takes place over vast distances and on a truly interstellar scale. I found there to be a surprising amount of “Sci” in this author’s brand of Military Sci-Fi, and more sense of wonder than I would typically associate with this kind of thing.

I have already mentioned the exotic tech described in this entry (and previous entries). Concepts like reality editing and the Quantum sea (a quantum base form with possibility waves that can affect reality) had me scratching my head a bit. In a good way, mind you, that’s why I read this kind of thing in the first place.

All in all, I found Semper Human to be a satisfying wrap up to the series.

He seemed to be within the eye of a storm, a vast and powerful storm of blue and violet light and mist, of half-glimpsed, half-sensed shapes and masses and unimaginable energies.
Profile Image for Little Timmy.
7,371 reviews58 followers
October 10, 2019
Normally at the end of a trilogy or series I not only rate the book but the set overall. This one is a bit different, its 3 trilogies that act both independently and as connected sets forming a series. They can be read as independent trilogies or as a running series. Each book in the trilogies is a 3/4 rating with the trilogies each being a solid 4 rating. However when taken as a whole the series is a easily a solid 5. It builds well upon itself not only within each trilogy but between trilogies and from the first to the last book. Good solid military SiFi stories with a nice plot and action that flows steady and smoothly throughout. The military feel of the characters and their personalities is spot on realistic from my perspective as a 21+ year Navy vet. If you want some nice action and some good future science theory in your story you will not go wrong picking this up. Highly recommended
268 reviews1 follower
December 21, 2016
Mon engagement auprès des Marines des 3 trilogies Heritage, Legacy et Inheritance se termine. Effectué d’une traite. Je mets 4 étoiles globalement. Malgré certaines formes narratrices répétitives, je me suis bien régalée dans cet univers. J’ai aimé son expansion de la lune et mars à toute la galaxie et au-delà, les humains qui n’arrivent pas au départ à faire face ensemble contre la menace Alien et se battent entre pays et factions, les combats contre les Xul avec une technologie de plus en plus puissante, le dévouement et le courage absolu des Marines, les descriptions de l’espace, les races Alien rencontrées au fur et à mesure jusqu’aux mystérieux Builders et jusqu’à One Mind, les projections scientifiques qui m’ont amenée à vérifier des théories ou chercher des précisions sur Internet, l’évolution de l’homme augmenté… L’homme est-il toujours humain ? La réponse sont les Marines, une fratrie de guerriers dont le seul but est de servir et protéger l’humanité,"forever vigilant, forever human" …. c’est dans cet esprit que j’ai dévoré les 9 livres. Sûrement, je lirai un peu plus tard Star Carrier l’autre série de l’auteur qui attend dans ma PAL.
3 reviews
February 22, 2019
End of the Beginning

Even though this is my 3rd reading of this book, I'm still wanting more. This book is written for the general reader who knows enough to be able to read this series without understanding all of the technology references. I quit trying to understand what exactly the Quantum sea was and how the galactic core black hole could be a encyclopedia for the universe, but I accept it. The writing is good enough that I understand, usually, what the concepts are and how they interact with each other, and how that (generally) relates to everything else.
Destroying the Xul is of paramount importance to this series. NOT becoming the NEXT Xul could be a good premise for the next series.
4 reviews
October 16, 2022
Semper human

Whilst an engrossing tome, much will be lost on those without a military background. Having been under the careful care and guard of the fine young troops of the 173rd MEU, I learned a certain respect for the Corps. This book does not who and what the USMC are, and does give a flavor of a far distant future
Profile Image for Timothy Haggerty.
230 reviews1 follower
December 7, 2021
Good series

I started this series with books 7, 8, and 9. I may go back and read the other six though I will know how it all work out. The final book wraps it all up nice and neat with our beloved Marines returning to Twenty Nine Palms which was the funniest part
Profile Image for David K.
11 reviews
October 11, 2014
After completing the Heritage, Inheritance, and now the Legacy trilogy, I can say the series was an enjoyable experience, though I probably should have read other books between each trilogy. I gave each book 4-5 stars because of how much I enjoy the genre and each books' execution of the idea on the whole despite the flows I found in them. There are four main flaws I noticed in Douglas' writing style in this series. One of these may have been slightly more visible because I read it on a Kindle which showed my progress by percentage.

The first issue for me was that these books became very formulaic and repetitive in their setup. Many chapters contained repetitive histories from both previous sections of the same book but also from the previous books throughout the trilogies and also Marine history. This created much "fluff" that could have been cut as it was unnecessary and the only reason to read it was because of variations in how it was written and occasional small details that were added. It was almost as though he was writing each book to meet a minimum page or word count for a publisher, or that each chapter was setup to be published separately as a short story on its own or in an anthology.

The second issue was that in using the ebook version on my Kindle the beginning of the climax in each book became very predictable at 80-85%. I would expect that this may have correlated loosely with page numbers as well.

***** SPOILERS *****





The third problem I had in these books was that despite the future fantasy setting they read like a very heavy handed recruiting commercial for the US Marines. The Marines role changed over time but mostly remained the USMC despite the overall, almost inevitable and more realistic, disappearance of the US instead of their persistence while humanity evolves into a galactic presence.

Last, the main characters necessarily changed in almost each book as the timeline had large jumps of centuries in the timeline, with the exception of in the first trilogy where there was a shorter timeframe involved. I think if he could have the author would have had the same characters throughout the entire series. Also, the names of the main characters changed over time, but the surnames persisted through most of the series, though toward the end they were incorporated into the first names, with recognizable corruptions of their spellings.
Profile Image for Andreas.
Author 1 book31 followers
May 1, 2011
After a thousand year “break” in the macrostory, the Marines are back. Revived from a centuries long hibernation (de facto a kind of reserve status), they wake to a radically different galactic society, with a plethora of alien races, as well as new offshoots of the human race. The reason for their awakening is that the Xul seem to be altering reality by subtly influencing human minds through the spooky effects of quantum physics.

After the breakneck action of the previous two books, this one feels very slow to start. A lot of time is spent discussing the changes to galactic society of the past centuries. The usual “Marines are anachronisms” message, only more so, and to excess. Once battle is joined, so to speak, it doesn’t feel anywhere near as visceral as previously. The characters are dull and lack the compelling qualities of those in earlier installments. Douglas redeems himself a bit at the end with some excellent historical vignettes, but it is not enough. Unfortunately, the book becomes one long treatise about why Marines have always pulled mankind’s (and in this case Galactic Society as whole’s) chestnuts out of the fire. While I understand and even agree with the message, it is far too heavy handed. So this ninth, and possibly last, book of the saga unfortunately ends it with a sizzle where there should have been a bang. A big, big bang.

http://www.books.rosboch.net/?p=656
Profile Image for Nathan Balyeat.
Author 1 book5 followers
December 16, 2009
The character development was never the strong point in this series, but it has continued to go downhill from the end of the first series. The constant reuse of Garroway and Warhurst family members to be the primary'voices' of the story has become grating as well.

The strong points of the series - action, speculative science, and speculative cultural development - are pretty stagnant compared to past books. I think that Douglas reached the point where he had to fit too much speculative science and cultural development into too little space, and by trying to do failed in that attempt, while also diluting the action.

I was satisfied with the read, but by no means excited. Despite the 2 star rating, I'd still buy the book again, but only because the series has a soft spot in my heart. As a stand alone novel If you evaluate a book by how fun it is to read on its own - good dialogue, good plot, exploring the human condition, etc, it's dreck.
Profile Image for Queldroma.
5 reviews
October 8, 2011
Though this book is not a great literary work, it does have some redeeming qualities. It is a great book if all you want is some action. The whole series is a constantly increasing action that I half expect them to start throwing planets at their foes(Oh wait they did that in the last book)then start throwing galaxies at each other in the name of spiral power.(Anime joke, if you did not get it it is ok )Much like the show I just referenced this book is written to be enjoyed with a light-heart and very little cerebral taxation. That is not to say it does not have an interesting message if you look very deep.

In the end it is a good action story much like a action film that will not win any awards but still enjoyable all the same in the right circumstance.
Profile Image for Michael.
1,235 reviews43 followers
February 5, 2017
This is the 3rd book in the Inheritance Trilogy by Ian Douglas a.k.a. William H. Keith Jr. In this one the Space Marines have voluntarily been put in to cybe-hibe sleep. 850 years have passed and they are awakened because they are once again needed to battle mankind's enemy the Xul. This time with the help of the modern Marine Corp they are going to try to put an end to the Xul threat once and for all. This is a great read and a good ending to this series about the Marines and their future as Earth's and all of mankind's defenders in the near and then the far future. I recommend it to all fans of Military Science Fiction and fans of Ian Douglas a.k.a. William H. Keith Jr.
Profile Image for Steven.
1 review
December 23, 2013
Great conclusion to a series that extends over a thousand years :) At first, "Semper Human" started slow, but then picked up. You get to know characters from the past and new ones. The epic finale gave great closure to the series and def leaves room for more add-on stories in the future. After this, I'm going to look into more of Ian Douglas's works.
Profile Image for Kevin.
191 reviews1 follower
February 11, 2025
The funniest thing in this entire series has to be when the Xul try to demoralize the marines by bombarding them with visions of the more unsavory moments from their most famous historical battles, but it doesn’t work because the marines know the “real” history of those battles and won’t allow the nuanced context of reality to cloud their glory. Like come on, man.
Profile Image for Ron.
4,055 reviews10 followers
March 8, 2012
The last in the ongoing trilogy of trilogies on the Space Marine vs Xul. It appears to be the end, but we will see if Ian Douglas comes up with another tale when he finishes with his Space Navy trilogy.
Profile Image for Don.
678 reviews
June 21, 2011
Book three takes place 1100 years after the end of the last volume in this series.

I actually liked this better than the last book, but the author still has a problem of repeating things.

Don't think I'll be reading any more from this writer.
2 reviews
March 18, 2012
A bit heavy reading on the quantum physics-side, but nevertheless an outstanding conclusion to a remakable series.
One of my must-read recommendation for every fan of scifi who also likes a plausible techonolgy in the future. (This goes for the complete series)
Profile Image for Steven Allen.
1,188 reviews23 followers
January 5, 2016
This was a good ending to the series. The final few pages felt a little rushed as if the author wanted to be done with the story and get it over with. Not a bad series but not one that I will keep or read again.
Profile Image for Steve.
44 reviews3 followers
November 20, 2009
Fast paced, testosterone fueled, space opera, with a cast of somewhat familiar characters...
2 reviews
Read
September 14, 2010
All three of the books in this trioligy (ok, kinda redundant) are excellent military science fiction, and rich in Marine Corps history and culture.
Profile Image for Micha.
169 reviews
February 28, 2016
I enjoyed the book and the overall story from previous books in this series. It was a little predictable at the end but still a good read.
Profile Image for Brian.
321 reviews17 followers
February 5, 2017
One of his best works so far. I am a fan for life!
Displaying 1 - 23 of 23 reviews

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