Beckham had been linked with a host of clubs since deciding to end a five-and-a-half-year stint in Major League Soccer.
Monaco were among those interested, but Paris St Germain fitted the bill for Beckham, with the veteran midfielder joining a team chasing the French league title and through to the last 16 of the Champions League where they will face Valencia.
PSG have been the biggest spending European club in the past year and Beckham will link up with other big money signings like Zlatan Ibrahimovic and Thiago Silva.
The Englishman received 12 formal offers from around the globe including South America, North America, South Africa, Russia, China and the Middle East as well as Europe before settling on the Ligue 1 outfit.
"Like I said, I've been very fortunate throughout my career," said Beckham.
Beckham was asked if the short-term deal would be his last as a player. "I don't know if it'll be my last contract," he said.
"People always speculate that it'll be my last but they've done that for a number of years and I continue to play and sign new contracts.
"I want to continue to play as long as possible.
"My passion is football. When I play football it's not about the biggest contracts.
"I want to play for the biggest teams and with the best players.
"If I can continue to do that at the highest level, then who knows?"
Discussing coach Ancelotti and president Leonardo's influence, Beckham said: "I'm very lucky to have worked with Carlo and Leo for quite a few months in Milan."
"Carlo is one of the best managers I've played for."
Asked how it felt, given his age, to be the 'grandpa' of Ligue 1, Beckham said: "It feels very good.
"To be the elder statesman... if I can give advice to any younger players then great.
"I still feel 21 most days so I'm very happy."
Beckham won back-to-back MLS Cups in the final two years of his spell in the United States, and is hoping to earn more silverware in his latest challenge, although there will be an initial hurdle to clear.
"I haven't spoken French since I was at school," he said. "I'm definitely going to have to brush up on it.
"But I'm excited. It's something we've been working on and talking about for quite a while but now it's finally happened."
His family will stay in London, with Beckham initially living out of a hotel.
Asked how much he could contribute on the pitch, Beckham said: "I have a lot of experience in the game; 37 years old; over 13 or 14 championships, trophies throughout my career; played for some of the biggest clubs in the world; played with some of the best players in the world; and still being successful at 37 years old and still being fit - I can run around and play like I could play when I was 21.
"I haven't lost any of my pace because I didn't have a lot of pace throughout my career, so that hasn't changed."
And while Beckham insisted PSG getting through the Champions League group stages was not the deciding factor in his choice, it offers him a chance to play at the highest level in club football again.
"It's a bonus that they're in the Champions League," he said. "I haven't played Champions League football for quite a few years.
"To be at a club that's in the Champions League is exciting for me.
"I've been lucky to win the Champions League once and know how important it is to the club.
"I'd have come if they weren't in the Champions League but I'm excited that they are."