CAIRO — Six years after roaring crowds ousted him at the peak of the Arab Spring, former President Hosni Mubarak of Egypt was freed early Friday from the Cairo hospital where he had been detained, capping a long and largely fruitless effort to hold him accountable for human rights abuses and endemic corruption during his three decades of rule.

Mubarak, 88, was taken under armed escort from the Maadi Military Hospital in southern Cairo, where he had been living under guard in a room with a view of the Nile, to his mansion in the upmarket suburb of Heliopolis.

His longtime lawyer, Farid el-Deeb, who has stewarded Mubarak through a tangled cluster of prosecutions since 2011, confirmed his release.

The release begins a third act for Mubarak, a once unassailable Arab ruler and US ally who came to power in 1981 after the assassination of President Anwar Sadat during a military parade. Thirty years later, Mubarak’s own rule ended abruptly as multitudes thronged Tahrir Square for 18 days in the heady, hopeful early months of the Arab Spring.

At the time, Mubarak’s fall seemed to signal a sea of change across the Arab world, shattering the established political order and suggesting that even its most powerful leaders were no longer immune from prosecution.

His release on Friday crowned the crushing of those hopes for change, and the enduring disappointment of the Egyptians who had risked their lives to topple him — even if many now say the challenge is far bigger than a single man.

Mubarak became the first Arab leader to face trial in a regular court in his own country. He was accused of having conspired with police to kill 239 protesters in Tahrir Square; having siphoned tens of millions of dollars from state coffers; and of having cut off the country’s Internet access during the 2011 uprising, among other crimes.

Despite the prosecution, Mubarak remained defiant, insisting that he, not the Egyptian people, had been wronged. His sons joined him in the dock, accused of having embezzled millions of dollars and having overseen a system of cronyism and graft.

But by then, it was becoming clear to many Egyptians that while Mubarak had gone, the system he controlled — with the military, security agencies, and courts in the background — remained firmly in place and would not cede power easily to restless protesters.

The first democratic election, in 2012, brought to power a leader of the Muslim Brotherhood, Mohammed Morsi. But he lasted only a year, making a series of political blunders that cost him the support of the military, crucial parts of the security apparatus, and millions of Egyptians, who gathered in the streets in June 2013 to call for his removal.

The military obliged on July 3 and installed Abdel-Fattah el-Sissi, its top commander, who cleared Brotherhood protesters from central Cairo with a massacre of at least 800 people by the security forces in August 2013. It signaled that no further uprisings would be tolerated, and Mubarak’s interminable trials seemed to reflect that change.

Public anger toward Mubarak faded to weariness as Egyptians turned to more pressing matters: el-Sissi’s harsh crackdown on his opponents, the emerging war against Islamic State group militants in the Sinai Peninsula, and a growing economic crisis.

After a 2012 conviction for the deaths of protesters, Mubarak was sentenced to life in prison. But an appeals court overturned that verdict and ordered a retrial, and he was exonerated. He also skirted several corruption accusations.

As the political will to pursue Mubarak dissipated, his supporters re-emerged in public, cheering him from the hospital gates on his birthdays and blowing kisses during courtroom hearings. Rowdy public protests against Mubarak fizzled under anti-protest laws introduced by el-Sissi.

But one charge stuck: that Mubarak and his sons had embezzled millions of dollars in state money. In May 2015, a court sentenced Mubarak and his sons to three years in prison each and ordered them to pay $20 million in restitution and fines. But they were allowed to count time served.

Mubarak’s legal woes are not entirely over. Thursday, a Cairo court created the basis for prosecutors to reopen a corruption probe into gifts that Mubarak received from a state-owned newspaper while in power.