I thought of more...
As you probably already know, in Western philosophy, from the time of Socrates and Plato (c. 470 B.C.E.) in Greece to even as late as the 1960s in the United States, women were not encouraged to engage in philosophy. In fact, they were not allowed to participate in political affairs in Greece; this was true even in America until the 1920s when women obtained suffrage rights. It took until 1980 for a female to be a candidate for Vice President.
The first females who wrote influential philosophical pieces, as far as I know, were Anne Conway (1631-1679), Mary Wollstonecraft (1759-1797), and Harriet Taylor (1807-1858). Anne Conway lived in Germany, wrote about God and the problem of evil, and it is presumed that Leibniz took some of her ideas and put it into his work Theodicy. Wollstonecraft and Taylor (wife of John Stuart Mill) both argued for equal rights for women.
You should know, however, that there are many female philosophers working now at universities, who have recently contributed and will continue to contribute much to the philosophical scholarship
Other female philosphers that I thought of:
Hypatia
Olympe de Gouges
Aspasia
Hrotsvit of Gaandersheim
Hildegard of Bingen
Margaret Beaufort
Sor Juana
de Genlis
Germaine de Staël
Belle van Zuylen
Gabrielle-Emilie du Châtelet
Angela Y. Davis
and there are still more that Im sure I missed