Raul Castro, who has walked alongside his brother Fidel at practically every turn since the Cuban Revolution, now must march into the future alone.
But he had already stepped out of the once-pervasive shadow of Fidel.
Raul, 85, has been in the driver's seat since an ailing Fidel "temporarily" ceded power to the then-defense minister in July 2006 and then succeeded Fidel as president of the Council of State and president of Cuba's Council of Ministers on Feb. 24, 2008.
He successfully navigated that potentially risky hand-over and embarked on a slow and steady stream of economic changes designed to ease the island's many economic woes.
The most dramatic change, however, came on Dec. 17, 2014, when Raul and President Barack Obama announced that Cuba and the United States would be resuming diplomatic ties after more than five decades of confrontational relations. The surprise announcement capped 18 months of highly secret talks facilitated by Canada, the Vatican and others that also resulted in a prisoner exchange, a Castro pledge to release 53 political prisoners and a U.S. commitment to liberalizing trade and travel to the island.
Obama and Castro had their first face-to-face meeting at the Summit of the Americas in Panama in April 2015, and the two countries finally restored diplomatic ties on July 20 of that year. A visit to Cuba by Obama this past March capped rapprochement efforts, but the American president proved so popular with the Cuban people that state media almost immediately began to downplay and criticize his visit.
Still, Cuban analysts have said they doubt a move toward normalization would have been possible with Fidel in control.
Under Raul, the Cuban government has rolled out economic reforms ranging from allowing worker-owned cooperatives and self-employment and the private sale of homes and autos to more free enterprise in agriculture, shifting state-owned restaurants into private hands and revamping the foreign investment law to woo international investors.
A major change that is extremely popular among Cubans is allowing most to travel abroad freely and remain outside the country for up to two years without losing citizenship rights.
But despite the more market-oriented reforms, Raul has steadfastly said Cuba's political model will remain intact.
"We shouldn't expect that in order for relations to improve with the United States, Cuba is renouncing the ideas for which we have fought for more than a century and for which our people have spilled so much blood and run such great risks," he said at the closing session of the National Assembly in December 2014.
Despite the diplomatic breakthrough two years ago, Raul has kept up a steady drumbeat against the U.S. embargo, which _ although weakened _ still remains in effect and can only be swept away by an act of Congress.
When it comes to economic change, Raul's catch phrase has been "sin prisa per sin pausa" (without haste but without pause). He "likes to experiment before moving forward and measure the results of the repercussions," said Domingo Amuchastegui, a former Cuban intelligence analyst.
Before assuming power, Raul was viewed with both trepidation and hope. He was expected to be harsher than Fidel on the political and security sides, but more pragmatic on the economic side and more likely to seek better relations with Washington _ and that is how it has played out.
The regime's tight political control of the island did not unravel, and he maintained continuity and stability.
Raul and his team would have moved faster to implement economic reforms had Fidel Castro not remained alive for so long, said Brian Latell, a former CIA Cuba specialist. Raul is known to admire Chinese- and Vietnamese-style economic reform.
One thing proved true: Raul, five years younger than his brother, governed first as an interim leader and then as Cuba's president without the flair and bombast of Fidel. He lacked the legendary magnetic personality his brother used to rule Cuba for almost 50 years.
Virtually everyone who knows Raul says his key personality trait is a capacity for organization, which makes him more flexible than the headstrong Fidel by allowing him to seek consensus and understand what's doable _ and what's not.
Latell said in his 2005 book, "After Fidel: The Inside Story of Castro's Regime and Cuba's Next Leader," that Fidel likely would not have stayed in power had it not been for Raul.
"I realized that Raul was his brother's one truly indispensable ally and that his brilliant, steady leadership of the Cuban armed forces secured the revolution," Latell wrote.
After the triumph of the Castro revolution in 1959, Raul used Soviet aid to build Cuba's Revolutionary Armed Forces, or FAR, into a powerful force that fought well in Angola, Ethiopia and several other foreign wars. And when the end of Soviet subsidies dramatically weakened the FAR in the early 1990s, Raul turned it into an economic powerhouse, running tourist hotels, managing imports and exports and eventually controlling an estimated 60 percent of the island's economy.
Analysts of the Cuban leadership concluded that, in times of trouble, Fidel always turned to Raul to make the tough decisions that ensured survival of the revolution.
Analysts say Raul is highly disciplined _ much more so than Fidel was.
One interesting take on Raul's personality came from Markus Wolf, the legendary spy chief of East Germany, in his 1997 autobiography "Man Without a Face."
"I found Raul ... steady, well-educated and statesmanlike," Wolf wrote. "Unlike his more emotional colleagues, he took a cool, strategic view of Cuba's situation. He was the only one there who turned up for appointments on time, a trait highly unusual for Cubans. His friends teased him for his punctuality and called him 'The Prussian.'"
But Raul, who once called himself "Raul the Terrible," can also be cold-hearted.
Within days of Fulgencio Batista's ouster from power in January of 1959, while Fidel enjoyed the adoration of crowds, troops under Raul's command in eastern Oriente province summarily executed about 100 Batista followers.
Armando Lago, the late Cuban exile economist who has made it his life's work to compile a list of every person killed in the name of the Cuban revolution, once said that as governor of the former Oriente province, Raul was personally responsible for 550 executions in 1959 alone _ about 100 of them without a trial.
It was also Raul who ordered the arrest of Gen. Arnaldo Ochoa, one of Cuba's most decorated and popular military officers _ apparently on orders from Fidel, who suspected him of disloyalty. Ochoa was executed in 1989 after he was convicted of drug smuggling in a nationally televised trial.
A former assistant to Raul's family, now living in Miami, said there's more than one side to his former boss. "He is not the cold monster many people think he is," the former aide told the Miami Herald.
Raul likes to party and enjoys telling and hearing jokes, is friendly to employees and aides and is far better than Fidel at taking care of family matters, the former secretary said. While Fidel missed their mother's funeral, Raul was the one who consoled the rest of the relatives. He seldom forgets a birthday.
