Darvish and Victor Caratini, who emerged as the right-hander's personal catcher in Chicago, will go to San Diego.
In return, the Cubs acquired right-hander Zach Davies and four young prospects: outfielders Owen Caissie (18) and Ismael Mena (18) and shortstops Reggie Preciado (17) and Yeison Santana (20).
Darvish, 34, is in the middle of six-year, $126 million contract he signed with the Cubs before the 2018 season. After an elbow injury sidelined him that year, he began to come into his own in 2019, leading to a stellar 2020 campaign. He compiled a 2.01 ERA and a 0.96 WHIP in 76 innings, finishing second in National League Cy Young Award voting to Trevor Bauer.
"His last season and a half has been as productive as anybody in the game. He's a force,'' Padres general manager A.J. Preller told reporters on Tuesday night.
Preller also said the team has been interested in Caratini "for a few years now."
"I think he's been a guy that, just on his own, we feel like is a quality catching option for us," Preller said.
The two star pitchers join Dinelson Lamet and Chris Paddack to form a formidable rotation in San Diego. Righty Mike Clevinger also is on the team but will miss the 2021 season after undergoing Tommy John surgery.
For the Cubs, the Darvish trade begins a reset under new president of baseball operations Jed Hoyer. That reset will include salary relief, as Darvish is owed $59 million over the next three seasons.
The team already non-tendered left fielder Kyle Schwarber, which also saved it money.
San Diego dipped into its deep well of prospects to fill Cubs coffers that have grown empty in recent years. All are long-term plays, full of tools and talent but exceedingly risky because of age and lack of playing experience.
Preciado, 17, might have the highest ceiling of the group after signing out of Panama in 2019. A 6-foot-4 shortstop who received $1.6 million, a record bonus for the country, he is a toolsy, switch-hitting athlete who international scouts believe was one of the best players in his signing class.
Caissie, another under-the-radar prospect, was a darling of computer models in the 2020 draft because of his age (he just turned 18), exit velocities (triple digits) and relative inexperience (he's from Ontario, Canada). Like Brennen Davis, the Cubs' top prospect, Caissie is a 6-foot-4 outfielder with excellent speed and athleticism -- and is the second top 2020 pick the Padres have traded in two days, with third-round bonus baby Cole Wilcox heading to Tampa Bay in the Snell trade.
The potential with Santana was clear in 2019, when he slashed .346/.429/.494 at 18 in the rookie-level Arizona League. Now 20, he is expected by scouts to stay at shortstop.
Mena signed in the same class as Preciado -- and for $600,000 more, at $2.2 million. At 6-foot-4 and 220 pounds, he's a classic A.J. Preller prospect -- full of tools and, if they develop, a star. He's the sort of player the Cubs need as their homegrown core nears free agency and the Cubs of 2016 become a distant memory.
The Associated Press contributed to this report.