On this day in history, Nazi leader Adolf Hitler violates the Treaty of Versailles and the Locarno Pact by sending German military forces into the Rhineland, a demilitarized zone along the Rhine River in western Germany.
In 1935, Hitler unilaterally canceled the military clauses of the treaty and in March 1936 denounced the Locarno Pact and began remilitarizing of the Rhineland. Two years later, Nazi Germany burst out of its territories, absorbing Austria and portions of Czechoslovakia.
In 1939, Hitler invaded Poland, leading to the outbreak of World War II in Europe.
On March 9, 1916, Germany declared war on Portugal, who earlier that year honored its alliance with Great Britain by seizing German ships anchored in Lisbon's harbor.
When World War I began in 1914, Portugal was a fledgling democratic republic, and newly elected president Manuel JosÉ de Arriaga was anxious about the security of Portugal's colonial holdings in Angola and Mozambique but desperate to remain neutral in the war.
In order to secure international support for its authority in Africa, Portugal begrudgingly entered the war on the side of Britain and the Allies. Its participation was at first limited to naval support, but by February of 1917, Portugal had 50,000 men stationed on the Western Front.