While baby car seats weren’t mandated by law in all 50 US states until 1986, they existed in some form for decades. Child seats for cars in the 1930s were among the first designed, though their purpose was primarily so kids could have a better view on car rides.
Infant car seats designed for safety didn’t come under consideration until the late 1960s, after concerned physicians and parents started pressuring auto manufacturers for improved safety features for children on seats and many other types of baby gear.