On This Day - What happened 12 September

Andronikos I Komnenos was finally overthrown when Isaac Angelos, surviving an imperial assassination attempt, seized power with the aid of the people and had Andronikos killed.

This period of renewed assertiveness came to a calamitous end in 1683 when Grand Vizier Kara Mustafa Pasha led a huge army to attempt a second Ottoman siege of Vienna in the Great Turkish War of 1683–1699. The final assault being fatally delayed, the Ottoman forces were swept away by allied Habsburg, German, and Polish forces spearheaded by the Polish king John III Sobieski at the Battle of Vienna.

Howe outmaneuvered Washington at the Battle of Brandywine on September 11, 1777, and marched unopposed into the nation's capital at Philadelphia. A Patriot attack failed against the British at Germantown in October. Major General Thomas Conway prompted some members of Congress (referred to as the Conway Cabal) to consider removing Washington from command because of the losses incurred at Philadelphia. Washington's supporters resisted and the matter was finally dropped after much deliberation. Once exposed, Conway wrote an apology to Washington, resigned, and returned to France.

Some nationalists feared that the new republic had descended into lawlessness, and they met together on September 11, 1786, at Annapolis to ask Congress to revise the Articles of Confederation. One of their biggest efforts, however, was getting Washington to attend.

In early September, Li Hongzhang decided to reinforce the Chinese forces at Pyongyang by employing the Beiyang fleet to escort transports to the mouth of the Taedong River. About 4,500 additional troops stationed in the Zhili were to be redeployed. On September 12, half of the troops embarked at Dagu on five specially chartered transports and headed to Dalian where two days later on September 14, they were joined by another 2,000 soldiers.

After the First Battle of the Marne (5–12 September 1914), Allied and German forces unsuccessfully tried to outflank each other, a series of manoeuvres later known as the "Race to the Sea". By the end of 1914, the opposing forces were left confronting each other along an uninterrupted line of entrenched positions from Alsace to Belgium's North Sea coast.

At a DAP meeting on 12 September 1919, Party Chairman Anton Drexler was impressed with Hitler's oratorical skills. He gave him a copy of his pamphlet (My Political Awakening), which contained anti-Semitic, nationalist, anti-capitalist, and anti-Marxist ideas.

On 12 September 1939, he attacked at Bitche, simultaneously with the Saar Offensive.

Mussolini was rescued by German troops from his prison in Campo Imperatore on 12 September 1943.

On 12 September 1944, King Peter II called on all Yugoslavs to come together under Tito's leadership and stated that those who did not were "traitors", by which time Tito was recognized by all Allied authorities (including the government-in-exile) as the Prime Minister of Yugoslavia, in addition to commander-in-chief of the Yugoslav forces.

Churchill met Roosevelt at the Second Quebec Conference (codename Octagon) from 12 to 16 September 1944. Between themselves, they reached an agreement on the Morgenthau Plan for the Allied occupation of Germany after the war, the intention of which was not only to demilitarise but also de-industrialize Germany.

The first practical ICs were invented by Jack Kilby at Texas Instruments and Robert Noyce at Fairchild Semiconductor. Kilby recorded his initial ideas concerning the integrated circuit in July 1958, successfully demonstrating the first working integrated example on 12 September 1958.

The final assignment for Armstrong in the Gemini program was as the back-up Command Pilot for Gemini 11, announced two days after the landing of Gemini 8. The launch was on September 12, 1966, with Conrad and Gordon on board, who successfully completed the mission objectives, while Armstrong served as a capsule communicator (CAPCOM).

On 13 September, central government workers in Tehran simultaneously went on strike.

Hoffa's wife, Josephine, died on September 12, 1980. She is entombed in Michigan.

On 12 September 2002, Jolie petitioned the court to legally remove her surname, Voight, in favor of her middle name, which she had long used as a stage name; the name change was granted.

In his first Champions League appearance for Inter, Ibrahimović was not able to avoid the 1–0 away defeat to Sporting CP as Inter began their European campaign in the wrong way.

On 12 September, he scored his first goal for the club on his Champions League debut against Werder Bremen.

Erdoğan visited Egypt on 12 September 2011, soon after Turkey had ejected Israeli ambassadors, cutting off all diplomatic relations with Israel because Israel refused to apologize for the Gaza flotilla raid which killed eight Turkish and one Turco-American. This was the first visit to Egypt by a Prime Minister of Turkey after the Egyptian Revolution of 2011.

Erdoğan also tightened controls over the internet, signing into law a bill which allows the government to block websites without prior court order on 12 September 2014. In November 2016, the Turkish government blocked access to social media in all of Turkey as well as bought to completely block internet access for the citizens in the Southeast of the country.

Although no longer serving as Prime Minister, Cameron originally stated that he would continue inside Parliament, on the Conservative backbenches. On 12 September, however, he announced that he was resigning his seat with immediate effect.

In 12 September 2017, IKEA announced the augmented reality app, IKEA Place, following by Apple's release of its ARkit technology and iOS 11. IKEA Place helps consumers to visualize true to scale IKEA products into real environment.

The third debate was held in Houston on September 12. In his opening statement, Yang promised to "give a Freedom Dividend of $1000 a month for an entire year to 10 American families". During the debate, he addressed topics including healthcare, immigration, foreign relations, the War on Terror, corporate lobbying, and education and charter schools. Yang spoke for a total of 7 minutes 54 seconds, which was again the least time of any candidate.

The King of Portugal, Afonso VI, passed away at the age of 40.

The American land owner, Frederick Philipse III, was born in New York City.