March 21 is the 80th day of the year (81st in leap years). There are 285 days remaining.
- 1945 — Willie Steelman is born.
- 1946 — Kenneth McDuff is born.
- 1948 — Jerry Walter McFadden is born.
- 1950 — Nathaniel Harvey is born.
- 1951 — Houston Roberts died.
- 1951 — Winford Stokes is born.
- 1954 — Mitchell Bacom is born.
- 1955 — Harvey Collins is apprehended.
- 1963 — Darryl Walters is born.
- 1963 — Frederick Charles Wood died.
- 1965 — Martina Authorlee (victim) is born.
- 1971 — Darren Vann is born.
- 1978 — Jeffrey Rignall is attacked by John Wayne Gacy.
- 1994 — Ann Bryan is murdered by Sean Vincent Gillis.
- 2000 — Robert Wayne Harris is apprehended.
- 2001 — Nikolai Kozlenya is apprehended.