President Donald Trump is directing that American flags be flown at half-staff for 30 days to honor the memory of former President George H.W. Bush.
In a proclamation signed Saturday hours after Bush died, Trump is also designating Wednesday as a national day of mourning. Trump encourages Americans to gather in places of worship "to pay homage" to Bush's memory.
When must a flag be lowered to half-staff? Though precedent is often followed, there are also guidelines outlined by President Dwight D. Eisenhower in a 1954 proclamation. Aside from the instances outlined by Eisenhower, the president can also choose to lower a flag whenever the nation is mourning, whether it is after a tragedy or after the death of another official not outlined in the proclamation.
If the flag at the White House is raised, the rest of the country is not required to follow the president's lead, according to the Official Guide to Government Information and Services. For instance, a school may choose to lower all of its flags to half-staff after the death of a student.
Here are all of the guidelines about how long to leave flags at half-staff, set out in Eisenhower's proclamation.
The Associated Press and ABC News contributed to this report.