'He played hard to get': Venus in winning return with Murray
Williams, playing her first event since Chicago in August last year, and Murray defeated Michael Venus and Alicja Rosolska 6-3, 6-7 (3/7), 6-3 in their first round clash.
The pair said their decision to play was last-minute but Williams revealed she had wanted to partner the Briton for some time.
"He played hard to get," she said. "I wanted to play with him for ages but it was super last-minute."
Williams said when she first arrived in London, it wasn't her intention to get back on the courts.
"I was at the French Open which is beautiful but my heart didn't beat the same way as when I saw the grass."
Williams, a five-time singles champion at Wimbledon, is a two-time Grand Slam mixed doubles champion.
However, both those titles came back in 1998 alongside Justin Gimelstob at the Australian Open and French Open.
She was runner-up in the mixed doubles at Wimbledon in 2006 with Bob Bryan.
Murray is a five-time Slam champion in the event, winning Wimbledon in 2007 and 2017 with Jelena Jankovic and Martina Hingis.
"I was supposed to play with Venus last year but I hurt my neck," said the 36-year-old.
"I couldn't say no twice. It was amazing to be on the court with such a champion."
Earlier this week Serena Williams and Andy Murray exited the singles.
Serena lost to unseeded French player Harmony Tan in her first singles match for a year.
Murray was defeated in the second round by John Isner.