Source is Wikipedia:
Bannon was a founding member of the board of
Breitbart News, a right-wing news, opinion and commentary website. Philip Elliott and Zeke J. Miller of
Time say the site has "pushed racist, sexist, xenophobic and anti-Semitic material into the vein of the
alternative right". Bannon said that Breitbart's ideological mix included libertarians, Zionists, the conservative gay community, same-sex marriage opponents, economic nationalists, populists, as well as alt-right, the alt-right comprising a very small proportion overall. Conceding the alt-right holds views with "racial and anti-Semitic overtones," Bannon said he has zero tolerance for such views.
In March 2012, after founder
Andrew Breitbart's death, Bannon became executive chair of Breitbart News LLC, the parent company of Breitbart News. Under his leadership, Breitbart took a more alt-right and nationalistic approach toward its agenda. In 2016, Bannon declared the website "the platform for the alt-right".Speaking about his role at Breitbart, Bannon said: "We think of ourselves as virulently anti-establishment, particularly 'anti-' the permanent political class."
In 2016 Breitbart News became a virtual rallying spot for supporters of
Donald Trump's 2016 presidential campaign. Breitbart's management, together with writer
Milo Yiannopoulos, solicited ideas for stories from, and worked to advance and market ideas of
neo-Nazi and white supremacist groups and individuals. After the election, more than 2,000 organizations removed Breitbart News from ad buys following
Internet activism campaigns denouncing the site's controversial positions.
On August 18, 2017, Breitbart announced that Bannon would return as executive chairman following his White House employment. On January 9, 2018, he stepped down as executive chairman.