The Dutchman competed in 10 grand prix with the Red Bull junior squad this year, having made a one-off appearance for Williams at the 2022 Italian Grand Prix in place of Alex Albon, finishing ninth.
But the 28-year-old endured a difficult 2023 campaign with AlphaTauri and was replaced by Daniel Ricciardo prior to the Hungarian Grand Prix in July, having failed to score any points during his tenure with the team.
De Vries claimed the 2020-21 Formula E title with Mercedes during a three-year spell at the team before the German manufacturer’s withdrawal at the end of 2022.
Mahindra endured a difficult campaign last term, scoring only one podium and finishing 10th in the teams' standings, but de Vries has been encouraged by the Indian manufacturer’s long-term vision.
“It feels like coming home in a way. Formula E is a very familiar environment for me, I see a lot of familiar faces from the championship, all the teams, all the drivers, so it’s nice to come back into a familiar environment,” de Vries exclusively told Autosport.
“I think it’s no secret that Mahindra did have a rough start to Gen3. I do think there was a good sign of progress throughout last season, although progress isn’t always measured just in results.
“But I was particularly excited about their future plans, about the changes that will be made in the due course but also the recruitments they’ve done.
"The plans in place to move up the grid and I think the fundamentals from the team have always been very strong.
“I personally have a lot of faith and positive encouragement by what the future is like. With the new plan and the changes that are made, I really believe we have a unique project.”
De Vries is joined at Mahindra by Mortara, both on multi-year deals, who left the Maserati MSG squad after six seasons with the outfit previously known as Venturi, during which time he claimed six wins that put him in championship contention during the 2020-21 and 2021-22 campaigns.
The decision to sign de Vries and Mortara means that Mahindra has parted ways with Lucas di Grassi, the Brazilian having been a mainstay of the all-electric championship since its inception in 2014.
He has yet to announce his racing plans for 2024 and whether he will remain on the Formula E grid, with pre-season testing due to get underway in Valencia the week commencing 23 October.
