19 May 1935: birth of Michael Wisher, who appeared as TV anchor Wakefield in The Ambassadors of Death (Third Doctor, 1970); factory owner Rex Farrel in Terror of the Autons (Third Doctor, 1971); Kalik in Carnival of Monsters (Third Doctor, 1973); most iconically as Davros in Genesis of the Daleks (Fourth Doctor, 1975); Magrik of the Vogans in Revenge of the Cybermen (also Fourth Doctor, 1975); Morelli in Planet of Evil (yet again, Fourth Doctor, 1975 - his third role in four stories); and Robar the ship's engineer in Shakedown (unofficial, 1994). A man of many faces, as you can see.
19 May 1944: birth of Colin Spaull, who played security chief Lilt in Revelation of the Daleks (Sixth Doctor, 1985) and Mr Crane in Rise of the Cybermen / The Age of Steel (Tenth Doctor, 2006).
19 May 1947: birth of Michael Cochrane, who played Charles Cranleigh in Black Orchid (Fifth Doctor, 1982) and Redvers Fenn-Cooper in Ghost Light (Seventh Doctor, 1989).
19 May 1982: death of Elwyn Jones, who is credited with co-writing The Highlanders (Second Doctor, 1966-67), though the lore is that in fact he didn't do any of the actual writing.
19 May 2006: death of Peter Bryant, script editor of Second Doctor era Who from the second half of Evil of the Daleks (1967) to The Enemy of the World (1967-68) and then producer from The Web of Fear (1968) to The Wheel in Space (1969).
ii) broadcast anniversaries
19 May 1973: broadcast of first episode of The Green Death. The Brigadier and Jo go to Llanairfach in Wales to explore why people are turning green.
19 May 2007: broadcast of 42. The Doctor and Martha have 42 minutes to save the S.S. Pentallian.