Event:
Pope Pius XII publishes encyclical Orientals Ecclesiae
More Notable Events on April 9:
1981 U.S. submarine George Washington rams Japanese freighter Nisso Maru
1970 Paul McCartney announces official split of Beatles
1967 1st Boeing 737 rolls out
1963 Winston Churchill becomes 1st honorary U.S. citizen
1912 Titanic leaves Queenstown, Ireland for New York
