That date was a Saturday.
October 12, 1964 fell on a Monday.
May 12, 1964 fell on a Tuesday.
Wednesday
It was a Wednesday.
It was a Thursday.
It was a Sunday.
April 12 1964 was a Sunday.
12 September 1787 was a Wednesday.
12 September 1947 was a Friday.
12 September 1998 was a Saturday.
September 12 1988 was a Monday.
September 12, 2012 was a Wednesday.