- Apr 5 Vincenzo Viviani, Italian mathematician (Viviani's theorem), born in Florence, Italy (d. 1703)
- Apr 7 Louise Hollandine, Abbess and painter, daughter of King Frederik V of the Palatinate and Elizabeth Stuart, born in Noordeinde Palace, The Hague (d. 1709)
- Apr 17 Henry Vaughan, English poet (Silex Scintillans), born in Newton St. Bridget, Brecknockshire, Wales (d. 1695)