Here is a summary of the Republic of Gilead as portrayed in that book (from Wikipedia):

-Beginning with a staged attack that kills the President and most of Congress, a Christian fundamentalist movement calling itself the "Sons of Jacob" launches a revolution and suspends the United States Constitution under the pretext of restoring order.

-They are quickly able to take away women's rights, largely attributed to financial records being stored electronically and labelled by gender.

-In Gilead, the bodies of women are politicized and controlled. The North American population is falling as more men and women become infertile (though in Gilead, legally, it is only women who can be the cause of infertility)

-African Americans have been relocated en masse to "National Homelands" in the Midwest, which are suggestive of the Apartheid-era homelands set up by South Africa

-Roman Catholics: nuns who refuse conversion to Christian Fundamentalism are considered "Unwomen" and banished to the Colonies due to their reluctance to marry and refusal/inability to bear children. Priests unwilling to convert are executed and hung from the Wall

-Jews refusing to convert to Christianity are allowed to emigrate to Israel, and most choose to leave. However, it's later revealed that many of the emigrating Jews ended up being dumped into the sea while on the ships ostensibly tasked with transporting them to Israel. Many Jews who chose to stay were caught secretly practicing Judaism and executed.

-In Gilead, women are the property of and subordinate to their husband, father, or head of household. They are not allowed to do anything that would grant them any power independent of this system. They are not allowed to vote, hold a job, read, possess money, or own anything, among many other restrictions

-Gilead's society values reproduction by white women most highly. The prevailing opinion is that women are considered intellectually and emotionally inferior to men.