Lieutenant General Ahmed Gaed Salah had become the most visible figure in Le Pouvoir - the "power," as Algerians describe their secretive ruling elite, helping to bring down long-time president Abdelaziz Bouteflika in April.
As military chief of staff, his strategy was to replace Bouteflika and his allies while keeping the essential structure of power unchanged and allowing the protests to continue, hoping to wait out the demonstrators.
Huge crowds continued to flood the streets through much of 2019 to demand wholesale change to the leadership, unappeased by Bouteflika's resignation and the arrest of many of his aides and allies on corruption charges.
The protest movement in the major oil- and gas-exporting country has no formal leaders or organization. But among its main demands throughout the weekly rallies has been that the army step away from its central political role since Algeria's 1962 independence from France, with marchers often chanting: "A civilian state, not a military state."
As the year wore on, protesters also increasingly called for Gaed Salah himself to resign, especially after he pushed hard for an election to replace Bouteflika that they regarded as illegitimate while the old guard still held sway.
The new president, Abdelmadjid Tebboune, quickly named the head of the land forces, General Said Chengriha, as the new acting chief of staff to replace Gaed Salah.
Chengriha, 74, is from the same generation of powerful generals as Gaed Salah, who was 79, both men having started their careers in the guerrilla forces that rose up against French colonial rule.
"The army hierarchy is unified and it will move on after Gaed Salah as it did before him. Algeria's army is a single bloc, not under the influence of one general but with consensus as its engine," said a retired general who asked not to be named.
Gaed Salah's death came at a critical moment in the state's response to the unrest. The army had pushed for the election of a new president as a big step in its strategy to restore a normal order in which it held a central role.
Though the protesters wanted Gaed Salah to step down and the army to walk away from politics, some prominent figures in their movement applauded the military's decision not to violently crush their demonstrations.
"(Gaed Salah) kept his promise to save the blood of Algerians during a tough period," Islam Benatia, a prominent figure in the protest movement, said on Facebook.
The funeral is expected to take place on Tuesday, a day on which students in the large North African country have been staging weekly protests for much of the year.
The protest movement is itself still debating its own response to President Tebboune's offer of dialog. It rejected his election through a vote in which official figures showed only 40% of voters took part.
Though Tebboune presented himself as independent, many protesters see him as a puppet for the military and immediately after his televised swearing-in last week he embraced Gaed Salah and awarded him an order of merit.
Weeks after the protests erupted early this year, Gaed Salah's televised speech urging Bouteflika to quit swiftly led to the veteran leader's resignation after 20 years in office.
The army then backed a series of arrests of Bouteflika allies and senior businessmen in an anti-corruption campaign that also functioned as a purge of the military's rivals within the ruling system.
Gaed Salah received military training in the Soviet Union and became head of Algeria's land forces in 1994, early in the civil war between the state and Islamist insurgents that killed 200,000 people.
Bouteflika appointed him army chief a decade later. In the past 15 years he consolidated the military's strength within the ruling elite, helping Bouteflika face down the once-dominant intelligence service.
As Bouteflika and his allies were ousted this year, the army's central role became more pronounced and Gaed Salah emerged as the most powerful figure in the country.