The Excertus Imperialis of the Great Crusade era was a vast organisation whose numbers in a literal sense are uncounted; no accurate measure of it has ever been possible, so numerous is it, widespread across the stars and in flux as units are disbanded or suffer attrition, and fresh units, recruits and indentures are added to its ranks. As a structure, it is almost unfathomably complex. It formed the incomprehensibly vast support?structure of the Great Crusade, including in its sweep the Expeditionary fleets' front line auxiliary and second line reserve forces (known collectively under the sub title of the Imperialis Auxilia一or Imperial Army informally) and the billions of planetary militia-raised provincial defence. It also included the myriad support organisations, colossal labour hosts, penitentiary legions, the warships and crew of the Imperialis Armada, the vast aexactory, Notary and Tithe corps, and nominally the Remembrancers, the Iterators and the enforcers of the Imperial truth—all were bound by its writ.?

大遠征時期的帝國民兵是個龐大的組織，他們的數(shù)量多到字面意義上的無法計算。他們的數(shù)量如此巨大，對他們的精確測量是字面意義上的不可能，他們廣泛分布在群星和不斷的征戰(zhàn)當中，隨著部隊解散或減員，新單位、新兵和契約兵被增添到了他們的部隊當中。作為一個組織，他幾乎是難以理解的復雜。他們組成了大遠征不可思議的支援組織，其中包括遍布遠征艦隊的前線輔助軍和二線預備隊（他們被統(tǒng)稱為帝國輔助軍，分正式稱呼為帝國軍）以及數(shù)以十億計的行星民兵防御部隊。他們也包括無數(shù)的支援組織、龐大的勞工集群、仲裁官軍團、帝國無敵艦隊的戰(zhàn)艦和船員、龐大的官僚集團、公證人和什一稅團、已經(jīng)名義上的記述者們——帝國真理的傳播者和執(zhí)行者，所有人都受帝國真理的法令約束。

Although notionally it was to the Officio Militaris on Terra and via them the Imperial Court to whom the numberless ranks of the Excertus Imperialis answered, it was always in truth subordinate to the principal agents and independent powers of the Great Crusade who commanded it on a daily basis: the Legiones Astartes and their Primarchs, the Mechanicum and their Titan Legions, the Knight Houses, the Rogue Traders Militant, the Imperial Commanders who governed the Imperiums worlds, the Navis Nobilite and the Collegia Psykana, all had better and more immediate call on the Excertus Imperialis to obey. So it was when the Imperium was riven by the Horus Heresy, so also was the Excertus Imperialis; turning traitor or remaining loyal with long accustomed masters to lead them, while even its more independent arms were forced abruptly to choose sides in a war not of their making. As the Great Crusade died, so did the organisation that served it, supplied it and fed its growth come to an end, split by division and torn in blood.

雖然在理論上，帝國民兵的無數(shù)部隊是聽令于泰拉上的軍務庭（機仆：后來叫軍務部）和帝國宮廷，但事實上，他們通常服從于那些每天指揮他們的大遠征主要施行者和獨立權威部門：阿斯塔特軍團與他們的原體，機械神教和他們的泰坦軍團，騎士家族，行商浪人的伍長，統(tǒng)治帝國世界的帝國指揮官們，導航者貴族和星語庭，所有能夠更為直接地命令帝國民兵服從自己的組織。所以，當?shù)蹏缓婶斔古褋y所撕裂時，帝國民兵們也被分為孑然分明的兩派：跟隨慣常領導著他們的主人們淪為叛徒或保持忠誠，甚至是那些更為獨立的部隊也突然要被迫在這場并非由他們挑起的戰(zhàn)爭中選擇自己的陣營。大遠征已死，那些曾服務于其的組織們亦然，他們曾支持和供養(yǎng)這場偉大的遠征，但現(xiàn)在一切都走向終結(jié)，分裂和鮮血撕裂了一切。