Namesakes
American First Ladies:
2 first ladies
Martha Washington 1789-1797 
Martha Jefferson Randolph 1801-1809
Biblical Characters:
1 character
Martha (f) Luke 10:38
Fictional Characters from Song Titles:
6 characters
(character) Martha 1967 Martha
(character) Martha 1968 Martha My Dear
(character) Martha 1972 Little Martha
(character) Martha 1988 Martha's Harbour
(character) Martha 1998 For Martha
(character) Martha 2010 Martha
Fictional Characters from Television:
3 characters
Martha Jones 1963 Doctor Who
Martha Logan 2001 24
Martha M. Masters 2004 House
Hurricanes and Tropical Storms:
1 hurricane
Hurricane Martha 1969
Notable Actors and Entertainers:
3 actors, 1 presenter
Martha Stewart 1941-
Martha Hackett 1961-
Yeardley Smith (a.k.a. Martha) 1964-
Martha Plimpton 1970-
Notable Businesspeople:
1 businessperson
Martha Stewart 1941-
Notable Explorers and Adventurers:
1 explorer
Calamity Jane (a.k.a. Martha) 1852-1903
Notable Journalists:
1 journalist
(journalist) Martha Gellhorn 1908-1998
Notable Musicians:
1 musician
Martha Argerich 1941-
Notable Philosophers and Thinkers:
1 philosopher
Martha Nussbaum 1947-
Olympic Medalists:
2 gold, 2 silver, 1 bronze
(gold) Martha Norelius 1924; 1928 swimming - 400 m freestyle; swimming - 4x100 m freestyle relay
(silver) Martha Genenger 1936 swimming - 200 m breaststroke
(gold) Martha Hudson 1960 4x100 m relay
(silver) Martha Langbein 1960 4x100 m relay
(bronze) Martha Randall 1964 swimming - 400 m medley
Other Royalty:
1 princess
Märtha Louise of Norway 1971- Norway
Rock and Roll Hall-of-Famers:
1 musician
Martha Reeves 1995 Martha and the Vandellas
Saints:
4 saints
Saint Martha of Bethany ?-80
Saint Martha ?-270
Saint Maura of Antinoe (a.k.a. Martha) ?-298
Saint Martha Wang Luo ?-1861