Short answers, pulled from the story.
Christian Democracy was founded on the 15th of December 1943 in Nazi-occupied Italy. It was disbanded on the 16th of January 1994 amid the Tangentopoli corruption scandals.
Christian Democracy's best result was the 1948 general election, when it won 48.5% of the vote and an absolute majority in the Italian Parliament. The party achieved this with the support of the Catholic Church and the United States.
Aldo Moro was the party's dominant leader and the architect of the Historic Compromise, an arrangement under which the DC governed from 1976 to 1979 with external support from the Italian Communist Party. He was abducted and killed by the Red Brigades in 1978.
Tangentopoli referred to a system of endemic corruption and bribery at the highest levels of Italian politics, uncovered beginning in 1992 by the Mani pulite investigation launched in Milan. The scandals triggered numerous arrests, resignations, and the eventual disbanding of the DC in 1994.
The party was nicknamed the White Whale, Balena bianca in Italian, because of its huge organisation and its official white colour. The nickname reflected both the party's size and its near-impossible-to-defeat dominance of Italian politics.
The DC's successor parties included the Italian People's Party, the Christian Democratic Centre, and the United Christian Democrats. Over subsequent years most former DC members joined Forza Italia on the centre-right, while the Italian People's Party eventually merged into the Democratic Party on the centre-left.