October 4, 1887 – Louisiana sugar workers went on strike, during which 37 unarmed black workers were murdered by Louisiana Militia, aided by bands of vigilantes. (From the Daily Bleed)
October 4, 1910 – 20 year old King Manuel II of Portugal was overthrown in a revolution. On October 7, the anti-church provisional government ordered all nuns and monks to leave the country. A republic was declared and the King fled to England. In 1908, the previous king had been assassinated.
October 4, 1946 – The U.S. Navy took over oil refineries to break a 20-state post-war wildcat strike.
October 4, 1989 - The United Mine Workers of America re-affiliated with the AFL-CIO, after decades of conflict with the organization. The UMWA had left the AFL in the 1930s when they refused to organize the auto and steel industries and played a pivotal role in the formation of the CIO. However, they withdrew from the CIO in 1942 in a dispute over labor-management relations during World War II. They were readmitted to the AFL in 1946, but left after a year when their president, John L. Lewis refused to sign the non-Communist affidavit required by the Taft-Hartley Labor Act. (From Workday Minnesota)