This is Book One of a five-book-plus series that may span decades of the main character’s life, as he struggles to do what is necessary among chaotic times.
The full series/storyline is more complex than twenty simple words can shrink it down to be, accurately. It is not "our" galaxy, but another one with many races (including humans), and common interstellar FTL travel, and technologies both mundane and wildly beyond the imagination.
An interstellar government, an Alliance of many stellar nations if you will, is hunting for a self-proclaimed Emperor who is capturing lone solar systems for some unknown purpose. The Alliance has its standing fleets, bases, academies, and the typical organizational-structuring that we might expect. These new Imperials also have a small but growing fleet dredged up from pirate forces, anti-Alliance dissidents, and assorted other malcontents; but they also have the advantage of secrecy, such that their "home base" is unknown, even while holding captive a number of systems.
The main character is a young man, not so unbelievably from a back-water planet; he is fresh out of high school and seeking to join the Alliace Fleet, by attending one of its academies. Orphaned soon after birth, he was raised not knowing his birth-parents, but by ingenuity and investigation had figured out who they were; his father had been a notable Fleet Admiral, his mother had been a disowned princess from a stellar nation that is still in contention with the Alliance. His parents had been murdered soon after his birth, due to the upstart-emperor’s primal underling’s interference and vengeance.
But his enlistment kicks off a series of events, both within Alliance Fleet hierarchy, and without. Some would like to use him for his father’s history or notoriety; others would like to dispose of him for his mother’s history or infamy. For his first semester break from Academy studies, he is taken under the provenance of the Academy commander, an aged admiral who knew his father and would like to shelter the boy from the greedy machinations of other officers, where the boy may learn things not taught in the Academy. Amid all this, on a simple Intelligence-gathering mission which doesn’t quite go as planned, our hero ends up in command of an independent merchant fleet which may not be what it claims, and more....