Literary scholar Michael Warner coined the term in 1991. It built on poet Adrienne Rich's 1980 essay on "compulsory heterosexuality," which argued that society pressures women into heterosexuality and treats it as the only natural choice.
Heteronormativity is often invisible to those it fits. It appears in forms with only "mother" and "father," in sex education that leaves out LGBTQ students, and in assumptions about who someone will marry. US law codified it in the Defense of Marriage Act of 1996, which defined marriage as between a man and a woman for federal purposes. The Supreme Court struck down that section in United States v. Windsor in 2013.
Heteronormativity is linked to racial norms too. Scholars such as Roderick Ferguson have argued that the 1965 Moynihan Report judged Black families as deviant for not matching the white, two-parent, male-headed household.