From 21 to 25 November 2015, the government of Belgium imposed a security lockdown on Brussels, including the closure of shops, schools, public transportation, due to information about potential terrorist attacks in the wake of the series of coordinated terrorist attacks in Paris by Islamic State of Iraq and the Levant on 13 November. One of the perpetrators of the attack, Belgian-born French national Salah Abdeslam, was thought to be hiding in the city. As a result of warnings of a serious and imminent threat, the terror alert level was raised to the highest level (four) across the Brussels metropolitan area, and people were advised not to congregate publicly, effectively putting the city under lockdown.

The Federal Government of Belgium (Dutch: Federale regering, French: Gouvernement fédéral, German: Föderalregierung) exercises executive power in the Kingdom of Belgium. It consists of ministers and secretary of state ("junior", or deputy-ministers who do not sit in the Council of Ministers) drawn from the political parties which form the governing coalition. The federal government is led by the Prime Minister of Belgium, and Ministers lead ministries of the government. Ministers together form the Council of Ministers, which is the supreme executive organ of the Government (equivalent to a cabinet).

Formally, executive power is vested in the King, who formally appoints the ministers. However, under the Constitution of Belgium, the King is not politically responsible for exercising his powers, but must exercise it through the ministers. The King's acts are not valid unless countersigned by a minister, and the countersigning minister assumes political responsibility for the act. Thus, in practice, the ministers do the actual day-to-day work of governing.