On the evening of June 28, 1969, patrons at the Stonewall bar in Greenwich Village resisted police during a raid. Without planning to, these patrons and others who fought back ignited a powerful social and political movement in the U.S. and abroad.

Cultural groups are marking the 40th anniversary of the Stonewall rebellion with exhibitions, talks, concerts and public celebrations. Stonewall marked the beginning of the modern gay rights movement, which would have a significant impact on the arts. New York City’s official visitors Web site features Rainbow Pilgrimage pages that point users to lesbian and gay landmarks and Pride Celebration events this week.

Writers, artists, historians and activists reflect on Stonewall in an online public forum on www.allianceforarts.org