Saga (noun)

1. A long story of heroic achievement, especially one concerning the early history of a people or a nation.
2. A prolonged and complicated series of events or a prolonged and complicated process.

Origin:

Mid 19th century: from old norse, "something said, a tale".

Examples:

1. The sagas of the Vikings are full of adventure and battles.
2. The building of the great wall was a saga that took years to complete.
3. The company's takeover was a long and complicated saga.
4. The love story between Romeo and Juliet is a classic saga.
5. The political scandal was a saga that lasted for months.