Mathematics Research Guide

(http://www.dcs.warwick.ac.uk/bshm/)
Its goals are to "promote research into the history of mathematics and its use at all levels of mathematics education." Links include Web Resources on the History of Mathematics(see link below).

(http://www.cshpm.org)
Founded in 1974, the society promotes research and teaching in the history and philosophy of mathematics. Many useful resources may be found on the History and Philosophy of Mathematics(see link below).

(http://www.maths.tcd.ie/pub/HistMath/HistMath.html)
Web pages on mathematicians from the 17th, 18th and 19th centuries.

(http://www.loc.gov/exhibits/vatican/math.html)
An exhibit showing that the Scientific Revolution of the 16th and 17th centuries had its foundation in Greek mathematics.

Contains the biographies of more than 1000 mathematicians as well as photos of approximately 500 mathematicians -- even has a link to an index of birthplace maps. Has an extensive History Topics page, including Prime numbers, Fermat's last theorem, Development of group theory, etc. (see 6 links below).

Math Alert and Math Alert Archives (see link below) from Mathematical Association of America (MAA) Online are made available at these two sites.

(http://www.mhs.ox.ac.uk)
Covers almost all aspects of the history of science, from antiquity to the early twentieth century -- particularly strong in their collection of scientific instruments, including early mathematical instruments -- Online exhibits include Compass and Rule: Architecture as Mathematical Practice in England, 1500-1750, The Measurers: A Flemish Image of Mathematics in the Sixteenth Century and The Geometry of War, 1500-1750 (see 4 links below).