Tuoba Ke was born in 483, as the second son of Emperor Xiaowen.

His mother was Xiaowen's concubine Consort, Gao Zhaorong. (As he was born the same year as his older brother Tuoba Xun, he was probably born just briefly after Tuoba Xun, whose mother was Consort Lin.)

Little is known about his childhood, including whether he was raised by his mother Gao or not.

Xiaowen in 496 changed the name of the imperial clan from Tuoba to Yuan, and thereafter he would be known as Yuan Ke.

Yuan Xun, who was in autumn 496 crown prince, but who could not endure the hot weather of the capital Luoyang after Xiaowen moved the capital there from Pingcheng in 494, plotted to flee back to Pingcheng with his followers, but his plot was discovered.

Xiaowen deposed him, and in 497 created Yuan Ke crown prince to replace Yuan Xun. (The creation was in Luoyang, but it is unclear whether prior to his creation, Yuan Xun was at Luoyang or Pingcheng.)

Gao, who was in Pingcheng, traveled south later that year to rejoin her son in Luoyang, but she died on the way.

Historians generally believe that she was murdered by Xiaowen's wife, Empress Feng Run, who wanted to raise Yuan Ke herself.

Whether she was actually able to do so is unclear, but after she is discovered to have carried on an affair with her attendant Gao Pusa in 499, she is put under house arrest, and Xiaowen orders Yuan Ke to have no more contact with her.

Xiaowen, while on a campaign against rival Southern Qi later in 499,  grows ill and dies.

Xiaowen's brother Yuan Xie the Prince of Pengcheng is placed in command of the withdrawing army on an emergency basis, and Yuan Xie keeps Xiaowen's death a secret while summoning Yuan Ke to join the army.

Yuan Ke's attendants largely suspect Yuan Xie of wanting to take the throne himself, but Yuan Xie, once he meets Yuan Ke, shows great deference to his nephew, persuading Yuan Ke of his loyalty.

Yuan Ke, at age sixteen, now assumes the throne as Xuanwu at Luyang (in modern Pingdingshan, Henan), before the army can return to Luoyang.

Xuanwu initially wants to make Yuan Xie, who is popular and well-regarded, prime minister, but Yuan Xie refuses, and is made a provincial governor instead.

The governmental affairs are largely in the hands of six officials: Xiaowen's brothers Yuan Xi the Prince of Xianyang and Yuan Xiang the Prince of Beihai, Xiaowen's cousin Yuan Cheng the Prince of Rencheng, Xiaowen's distant uncle Yuan Jia the Prince of Guangyang, and the officials Wang Su and Song Bian, although Yuan Cheng was soon stripped of his post because he falsely arrested Wang on suspicion of treason.

Xuanwu, once he returns to Luoyang, posthumously honors his mother Gao as an empress, and he createdshis maternal uncles Gao Zhao and Gao Xian, as well as his cousin Gao Meng, none of whom he had previously met, dukes.

Gao Zhao, in particular, will become increasingly powerful during Xuanwu's reign.

Xuanwu recalls Yuan Xie by 500 to be prime minister.

With Southern Qi in disarray because of the tyrannical rule of its emperor Xiao Baojuan, Northern Wei annexes the important city of Shouyang (in modern Lu'an, Anhui) when the Southern Qi general Pei Shuye surrenders the city to Northern Wei in fear of adverse actions by Xiao Baojuan.

However, Northern Wei does not take further actions when Southern Qi is subsequently thrown into civil war during the rebellions of the generals Cui Huijing and Xiao Yan.

The general Yu Lie and Yuan Xiang warn Xuanwu in 501 that Yuan Xi is growing corrupt and Yuan Xie is growing too popular, and suggests that they be relieved of their posts.

Xuanwu does so, and formally personally takes over governmental matters, but at his age, he cannot actually properly handle governmental affairs himself, so his trusted attendants and Gao Zhao begin to become more powerful and corrupt.

Traditional historians generally regard this as the starting point of Northern Wei's decline.

Late in 501, Yuan Xi, displeased that his power is being stripped and fearful that he will be killed, plots a rebellion to secede with the provinces south of the Yellow River.

His plot is discovered, however, and he is executed.

From this point on, Xuanwu grows increasingly suspicious of members of the imperial clan.

Later in 501, Xuanwu creates Yu Lie's niece, Consort Yu, empress.

Near the end of the year, with Xiao Yan's forces crushing Xiao Baojuan's, Xuanwu's general Yuan Ying suggests that a major attack be launched against Southern Qi to take advantage of Southern Qi's civil war.

However, Xuanwu only authorizes small scale attacks, which are generally fruitless.

Xiao Yan soon defeats Xiao Baojuan and by 502 has overthrown Southern Qi and established the Liang Dynasty as its Emperor Wu.

The Liang general Chen Bozhi subsequently tries to surrender Jiang Province (modern Jiangxi and Fujian) to Northern Wei, but Liang forces defeat both Chen and the Northern Wei forces sent to reinforce him, and Chen flees to Northern Wei.

For the next few years, however, there will continually be war between the two rivals, particularly with Northern Wei creating Southern Qi's prince Xiao Baoyin, who flees Southern Qi as Xiao Yan is beginning to kill members of the Southern Qi imperial clan, naming him the Prince of Qi and announcing that it will help him reestablish Southern Qi.

Xuan Xiang, who has taken over Yuan Xi's posts, is in 504 accused by Gao Zhao of corruption, demoted to commoner rank, and dies soon thereafter.

At Gao's suggestion and despite Yuan Xie's opposition, Xuanwu subsequently puts the imperial princes under heavy guard, effectively putting them under house arrest.

The wars with Liang continue, and while both sides have gains and losses, Northern Wei makes a substantial gain in 505 when the Liang general Xiaohou Daoqian surrenders Nanzheng (in modern Hanzhong, Shaanxi), as well as the surrounding region, to Northern Wei.

Liang launches a major counterattack in winter 505 on the eastern part of the border, commanded by Emperor Wu's brother Xiao Hong the Prince of Linchuan.

Northern Wei annexes the semi-independent Di state of Chouchi in spring 506.

Xiao Hong being an incompetent general, who mishandles a night terror situation in summer 506, while his army is at Luokou (in modern Bangbu, Anhui), the Liang forces collapse by themselves without engaging Northern Wei forces.

Yuan Ying and Xiao Baoyin follow up by attacking the Liang fortress Zhongli in modern Chuzhou, Anhui), but are dealt a crushing defeat by the Liang general Wei Rui in spring 507.

The two states largely stop their military activities against each other after this point.