According to historical evidence, Vindication was written in 1792 as a direct response to a report given to the French National Assembly in 1791 that women should receive only a "domestic education". The book was written to attack this double standard. At its premise is the idea that although women are physically inferior to men, any reason for a rational inferiority is the fault of education and not nature. Therefore, women should be provided with the same rational-based education as men are, particularly since they are to be raising the next generation of citizens. Her argument is that women are being raised solely to be alluring and obedient to men, and consequently have no notion of how to raise children or organize a household.
Although the book was written a good 20 years before Jane Austen published her first novel (Sense and Sensibility, in 1811), in my reading of the Vindication I have naturally envisioned Wollstonecraft writing to women during the Regency period. Perhaps that is because the book is addressed towards the upper-class women of Britain. Furthermore, having read a fair amount of Regency-era literature, particularly so-called "drawing room romances", I am familiar with the excesses of sensibility that were exhibited by "elegant" and "refined" women during Austen's time.
Of interesting note is the life story of the author herself, which was documented in a posthumous memoir published by Wollstonecraft's husband. Initially against the institution of marriage, Wollstonecraft had two passionate love affairs. After her affair with Gilbert Imlay (with whom she had a daughter) ended, Wollstonecraft attempted twice to commit suicide. In the years after this affair, she eventually wed William Godwin, who was one of the forefathers of the anarchist movement. In brief, even while Vindication advocates a life of reason and rationalism for women, Wollstonecraft's own life was anything but conventional.
I will admit to being far more enamored by Wollstonecraft's unconventional life than I am by her treatise on female education!