What happened October 1987 AD

In October 1987, the UP's 1986 presidential candidate Jaime Pardo Leal was assassinated amid a wave of violence that would lead to the deaths of thousands of its party members at the hands of death squads. According to Pecáut, the killers included members of the military and the political class who had opposed Belisario Betancur's peace process and considered the UP to be little more than a "facade" for FARC, as well as drug traffickers and landowners who were also involved in the establishment of paramilitary groups.

In the United Kingdom, Black History Month was first celebrated in October 1987. It was organised through the leadership of Ghanaian analyst Akyaaba Addai-Sebo, who had served as a coordinator of special projects for the Greater London Council (GLC) and created a collaboration to get it underway.

On October 17, 1987, about 3,000 Armenians demonstrated in Yerevan complaining about the condition of Lake Sevan, the Nairit chemicals plant, and the Metsamor Nuclear Power Plant, and air pollution in Yerevan.

Iran deployed Silkworm missiles to attack some ships, but only a few were actually fired, and in response to Iranian Silkworm missile attacks on Kuwaiti oil tankers, launched Operation Nimble Archer, destroying two Iranian oil rigs in the Persian Gulf.

On October 19, 1987, the Dow Jones Industrial Average (DJIA) dropped 508 points, a 22.6% loss in a single day, the second-biggest one-day drop the exchange had experienced. Black Monday was followed by Terrible Tuesday, a day in which the Exchange's systems did not perform well and some people had difficulty completing their trades.

On October 21, a demonstration dedicated to those who gave their lives in the 1918–1920 Estonian War of Independence took place in Võru, which culminated in a conflict with the militia. For the first time in years, the blue, black, and white national tricolor was publicly displayed.