Michael Wear met local politicians, businessmen and charity representatives as he launched the Cathedral Innovation Centre (CIC).
The new centre, based next to St Joseph’s Church in Bugle Street, will offer start-up space in Bernard Street and help for people wanting to establish start-ups in the city.
It is the second innovation centre in Hampshire, after one opened in Portsmouth last year.
Mr Wear was an adviser to Mr Obama on his successful re-election campaign in 2012, specialising on “faith outreach” work with religious communities.
While at the new centre, which has been set up in partnership with Totton College, he met Fareham MP Mark Hoban, Southampton city councillor Satvir Kaur and Monsignor Vincent Harvey, head of the city’s Catholic church, as well as members of Southampton City Mission and Love Southampton.
CIC founder Francis Davis said: “The room was packed with voluntary sector, business and faith activists from all communities and all parties to celebrate the centre’s progress and learn from Michael.”