Short answers, pulled from the story.
Marcus Licinius Crassus (115-53 BC) was a Roman general and statesman widely called "the richest man in Rome." He played a central role in the First Triumvirate alongside Julius Caesar and Pompey the Great, and his death at the Battle of Carrhae in 53 BC removed the political counterbalance between Caesar and Pompey, contributing to the civil war that followed within four years.
Crassus built his wealth through several methods: acquiring proscribed property cheaply after Sulla's civil war, speculative real estate purchases, slave trafficking, and silver mine production. Most notoriously, he created a private 500-man fire brigade that would only extinguish fires after the distressed owner sold the burning building to Crassus at a low price. Plutarch estimated his total wealth at 7,100 talents of silver.
Crassus was given command against Spartacus after multiple Roman legions had been defeated. He revived the ancient punishment of decimation to restore his troops' discipline, built a ditch and rampart across the Bruttium peninsula to trap the slave armies, and won the decisive battle at the Silarius river in 71 BC. He then ordered the six thousand surviving captured slaves crucified along the Via Appia.
The First Triumvirate was an informal political alliance formed in 60 BC between Crassus, Pompey the Great, and Julius Caesar, who became consul in 59 BC. Crassus had been Caesar's financial patron, funding his election as pontifex maximus, and Caesar brokered the arrangement between Crassus and Pompey, who personally disliked each other. The alliance was restabilized at the Luca Conference in 56 BC and lasted until Crassus' death.
Crassus died in 53 BC following his defeat at Carrhae, in modern Turkey. After his legions were devastated by Parthian horse archers and retreated to the city of Carrhae, his men demanded he meet the Parthian general Surena to negotiate. When Crassus mounted his horse to ride to the Parthian camp, a scuffle broke out after his officer Octavius grabbed his bridle suspecting a trap, and every Roman present was killed.
According to Plutarch, Crassus' head was brought to the Armenian capital of Artashat during the wedding celebration of the Parthian king Orodes II's son Pacorus to the sister of the Armenian king Artavasdes II. While both kings watched a performance of Euripides' Bacchae, an actor named Jason of Tralles used Crassus' head as a stage prop in place of Pentheus' head.