It Means it "obligatory" or "mandatory.
Ex. It is complusory that you go to class
a large area rich in mineral deposits
Robert e. lee
a Jewish officer in the French army
the catholic church
most middle-class men
World War 1
All adult males were allowed to vote.
Between 6,000 and 7,000 confirmed, with estimates as high as 20,000
refused to reopen the case
Evidence came to light in 1896-primarily through an investigation instigated by Georges Picquart, head of counter-espionage-identifying a French Army major named Ferdinand Walsin Esterhazy as the real culprit. After high-ranking military officials suppressed the new evidence, a military court unanimously acquitted Esterhazy after a trial lasting only two days.
Many people wanted Monarchy
Ulysses S. Grant
Porfirio Diaz (1830-1915)
The Mexican-American War was about which country owns Texas.
You got it all wrong: Mexico City is in the country of Mexico, and it is the capital of such country. On the other hand, New Mexico was a territory of Mexico and was named in honor of such country.
New Mexico now is part of the United States because there was a war between Mexico and the United States from 1846 to 1848, and Mexico lost such war; as a result New Mexico became a territory of the United States and become a state in 1912.
Napoleon III was Napoleon I's nephew.