18世纪没有多少军事革新，在武器、战术及指挥水平方面只有缓慢的进步。步兵仍排成紧密的纵队前进，然后近距离作战。不过，步兵对抗骑兵的能力有所增强。很长时间以来，步兵对付骑兵最好的武器是长矛。在18世纪初期引进了刺刀之后，长矛就被刺刀取代了。这样，持滑膛枪作战的步兵就可以用刺刀来保护自己，炮兵的建设更为标准化，行动更为灵活。火力和射程极具威力的大炮开始在战场上起主导作用，成为主要的士兵杀手。

19世纪下半叶，战争发生了巨大的变化。直到1840年，部队使用的武器和采取的作战方式仍与一个世纪前相差无几，而到1900年时，战争几乎发生了天翻地覆的变化。当时出现了很多新型的武器，部署和指挥战斗的是职业军官，而且铁路和电报系统也得到了运用。这些变化都使战争更有计划性，更具控制力和杀伤力。在战场上谁的武器火力更猛，谁的调动速度更快，谁就更可能赢得战争的胜利。

18世纪，随着燧发枪和刺刀这两项军事新发明在欧洲军队中的大量装备，火药武器终于彻底统治战场，常备军时代来临了。此后，手持燧发枪，排着整齐横队，在鼓点声中直面敌人炮火的线式步兵成为欧洲战场上的主力。欧洲人正是在线式战术时代，通过大北方战争、西班牙王位继承战争、四国联盟战争、波兰王位继承战争、奥地利王位继承战争、七年战争以及拿破仑战争的不断洗礼和冲击，才终于确立起了在全球领域内的军事霸权，并成为日后全世界争相效仿学习的典范。

With On to Petersburg, Gordon C. Rhea completes his much-lauded history of the Overland Campaign, a series of Civil War battles fought between Generals Ulysses S. Grant and Robert E. Lee in southeastern Virginia in the spring of 1864. Having previously covered the campaign in his magisterial volumes on The Battle of the Wilderness, The Battles for Spotsylvania Court House and the Road to Yellow Tavern, To the North Anna River, and Cold Harbor, Rhea ends this series with a comprehensive account of the last twelve days of the campaign, which concluded with the beginning of the siege of Petersburg.
On to Petersburg follows the Union army’s movement to the James River, the military response from the Confederates, and the initial assault on Petersburg, which Rhea suggests marked the true end of the Overland Campaign. Beginning his account in the immediate aftermath of Grant’s three-day attack on Confederate troops at Cold Harbor, Rhea argues that the Union general’s primary goal was not―as often supposed―to take Richmond, but rather to destroy Lee’s army by closing off its retreat routes and disrupting its supply chains. While Grant struggled at times to communicate strategic objectives to his subordinates and to adapt his army to a faster-paced, more flexible style of warfare, Rhea suggests that the general successfully shifted the military landscape in the Union’s favor.
On the rebel side, Lee and his staff predicted rightly that Grant would attempt to cross the James River and lay siege to the Army of Northern Virginia while simultaneously targeting Confederate supply lines. Rhea examines how Lee, facing a better-provisioned army whose troops outnumbered Lee’s two to one, consistently fought the Union army to an impasse, employing risky, innovative field tactics to counter Grant’s forces.
Like the four volumes that preceded it, On to Petersburg represents decades of research and scholarship and will stand as the most authoritative history of the final battles in the campaign.