Clegg will take up the position on Monday (22 October), before moving to the firm's HQ in Silicon Valley in January with his family. He succeeds Elliot Schrage, who announced in June that he would leave Facebook after a decade, but continues at Facebook as an advisor.
A Financial Times report claims Clegg – who will report to COO Sheryl Sandberg – agreed to take on the job 'after months of wooing' by Facebook CEO Mark Zuckerberg, who told him he would 'have a leading role in shaping the company’s strategy'.
In August Facebook lost its VP of communications for WhatsApp, Instagram, and Messenger Rachel Whetstone, to Netflix, despite her being tipped as a contender to replace Schrage.
In a post on his new employer's network, Clegg wrote: "I am delighted to be joining Facebook. After almost twenty years in European and British politics, this is an exciting new adventure for me.
"Having spoken at length to Mark and Sheryl over the last few months, I have been struck by their recognition that the company is on a journey which brings new responsibilities not only to the users of Facebook’s apps but to society at large. I hope I will be able to play a role in helping to navigate that journey."
He continued: "Facebook, WhatsApp, Messenger, Oculus and Instagram are at the heart of so many people’s everyday lives – but also at the heart of some of the most complex and difficult questions we face as a society: the privacy of the individual; the integrity of our democratic process; the tensions between local cultures and the global internet; the balance between free speech and prohibited content; the power and concerns around artificial intelligence; and the wellbeing of our children.
"Throughout my public life I have relished grappling with difficult and controversial issues and seeking to communicate them to others. I hope to use some of those skills in my new role."
Sandberg stated: "I’m excited to announce that Nick Clegg is joining Facebook as VP, global affairs and communications. He is a thoughtful and gifted leader who has served as a Member of the European Parliament, a British MP and Deputy Prime Minister of the UK, and understands deeply the responsibilities we have to people who use our service around the world."
"Our company is on a critical journey," she continued. "The challenges we face are serious and clear and now more than ever we need new perspectives to help us though this time of change. The opportunities are clear too. Every day people use our apps to connect with family and friends and make a difference in their communities. If we can honor the trust they put in us and live up to our responsibilities, we can help more people use technology to do good.
"That’s what motivates our teams and from all my conversations with Nick, it’s clear that he believes in this as well. His experience and ability to work through complex issues will be invaluable in the years to come."
Before losing his seat in last year's general election, Clegg was MP for Sheffield Hallam from 2005. He replaced Richard Allan (now Lord Allan), who went on to join Facebook in 2009, where he is vice-president of public policy for EMEA.
Earlier this week, Facebook announced a range of transparency measures including demands that UK political advertisers verify their identity on its platform.
Clegg joins in the year of the "techlash", during which Facebook has suffered a six per cent decline in brand value compared with 2017 – in the wake of the Cambridge Analytica data misuse scandal - according to Interbrand's 2018 Best Global Brands report.