- May 4 Battle of Etampes: French army under Turenne beats Fronde rebels
- May 10 John Johnson, a free African American, is granted 550 acres in Northampton, Virginia
- May 13 Ingen Ryuki invited to become the abbot of Sofokuji temple in Nagasaki
- May 18 Rhode Island enacts 1st law declaring slavery illegal
- May 19 Spanish troops occupy Grevelingen
- May 29 Battle of Goodwin Sands, off Folkestone, Kent: English 'General at Sea' Robert Blake drives out Dutch fleet under Lieutenant Admiral Maarten Tromp