The Republic of German-Austria signs the Treaty of Saint-Germain-en-Laye, ceding significant territories to Italy, Yugoslavia, and Czechoslovakia. Date: September 10, 1919 Read more on Wikipedia → 📅 Other events on September 10 📅 Events on this day in 1919 📅 On This Day (Today)

The New York City Subway's third competing subway system, the municipally owned IND, is opened. Date: September 10, 1932 Read more on Wikipedia → 📅 Other events on September 10 📅 Events on this day in 1932 📅 On This Day (Today)

The first world individual Speedway World Championship was held at London's Wembley Stadium. Date: September 10, 1936 Read more on Wikipedia → 📅 Other events on September 10 📅 Events on this day in 1936 📅 On This Day (Today)

Nine nations attend the Nyon Conference to address international piracy in the Mediterranean Sea. Date: September 10, 1937 Read more on Wikipedia → 📅 Other events on September 10 📅 Events on this day in 1937 📅 On This Day (Today)

World War II: The Canadian declaration of war on Germany receives royal assent. Date: September 10, 1939 Read more on Wikipedia → 📅 Other events on September 10 📅 Events on this day in 1939 📅 On This Day (Today)

World War II: The submarine HMS Oxley is mistakenly sunk by the submarine HMS Triton near Norway and becomes the Royal Navy's first loss of a submarine in the war. Date: September 10, 1939 Read more on Wikipedia → 📅 Other events on September 10 📅 Events on this day in 1939 📅 On This Day (Today)

World War II: The British Army carries out an amphibious landing on Madagascar to re-launch Allied offensive operations in the Madagascar Campaign. Date: September 10, 1942 Read more on Wikipedia → 📅 Other events on September 10 📅 Events on this day in 1942 📅 On This Day (Today)

World War II: In the course of Operation Achse, German troops begin their occupation of Rome. Date: September 10, 1943 Read more on Wikipedia → 📅 Other events on September 10 📅 Events on this day in 1943 📅 On This Day (Today)

At the Summer Olympics in Rome, Abebe Bikila becomes the first sub-Saharan African to win a gold medal, winning the marathon in bare feet. Date: September 10, 1960 Read more on Wikipedia → 📅 Other events on September 10 📅 Events on this day in 1960 📅 On This Day (Today)

In the Italian Grand Prix, a crash causes the death of German Formula One driver Wolfgang von Trips and 15 spectators who are hit by his Ferrari, the deadliest accident in F1 history. Date: September 10, 1961 Read more on Wikipedia → 📅 Other events on September 10 📅 Events on this day in 1961…