Marcus is one of three vampire leaders of the Volturi in Volterra, who live what Edward described as a very civilized and educated lifestyle. Carlisle found them while on his own search for the truth behind his nature. The Italian vampires tried to cure Carlisle of "his aversion to his natural food source," but they failed. Their likeness was depicted in several paintings by Solimena.
Added by Volturifan199
After Marcus became a vampire, he met Aro and became part of the Volturi before Didyme, who was Aro’s biological sister, and fell in love with her. Didyme was blessed with the ability that wasn’t anything like Aro’s, and it was to make people happy. Marcus and Didyme eventually became discontent with the Volturi, and planned on leaving. In order to prevent leaving the Volturi, Aro, who pretended to give his blessing, killed Didyme in order to keep Marcus there because he was too integral to his plans to lose. Marcus never found out what Aro did to Didyme, and afterward Aro had Chelsea use her ability to ensure Marcus remained loyal to the Volturi. By 500 AD, the Volturi had usurped control of the vampire world from the Romanian Coven. Aro ruled the Volturi, along with Marcus and Caius, although he generally acted as spokesperson. The Volturi, under the three ancients’ control and leadership, set down the laws of the vampire world and cruelly punished those who did not follow to them. Carlisle Cullen came to live with the Volturi for some time. The Volturi, as well as a majority of the vampire species, did not understand Carlisle's "vegetarian" lifestyle and tried to convert him to human blood; they failed to do so. After staying with the Volturi for a decade, Carlisle decided to leave for the New World.
Marcus, as well as the rest of the Volturi, are both feared and respected throughout the vampire world as the guardians who keep the human world ignorant of the supernatural. He is also known to be respected in the human world as "Saint Marcus", the holy priest who drove all the vampires from Volterra. His national holiday, St. Marcus Day, is celebrated each year by the people of Volterra. The legend most likely developed out the fact that the Volturi do not permit hunting within the walls of Volterra.
- Main article: New Moon
Added by Volturifan199
At one point, Edward Cullen, one of Carlisle’s adopted children, comes to the Volturi because he believed that his love, Bella Swan, had committed suicide, and was thus suicidal himself. Aro was interested in Edward’s mind reading from a distance, and told him that it was a waste to kill him. After Edward’s suicide attempt, Marcus met Bella and was surprised with the closeness of her relationship with Edward, which reminded himself of his relationship with Didyme. One touch with Aro revealed this information. It was decided by the end that Bella should become a vampire.
- Main article: Eclipse
- Main article: Breaking Dawn
Sometime after Bella becomes a vampire, Irina, a vampire from the Denali Coven, comes to Volterra to tell the Volturi that the Cullens have created a immortal child. The Volturi responded by gathering an army and the entire guard (including the wives) to destroy the Cullens. When the Volturi arrived, Marcus, Aro, Caius and the others were surprised that the Cullens assembled to oppose them, thus furthering Aro's belief that they have created an immortal child. The Volturi stopped launching an attack when they start seeing the werewolves. After reading Edward’s mind about Renesmee, the so-called immortal child, he found himself astonished and delighted to discover that she is actually a vampire-human hybrid. The Volturi put to a vote on whether or not Renesmee should be killed because Caius didn’t know if she would become a threat to the exposure of the vampire community. It was voted to let her be until they know if she is a danger to the vampire world. Marcus was the only known one to vote against Renesmee being destroyed. Alice Cullen and Jasper Hale show up with another vampire half-breed named Nahuel, who gave the Volturi the excuse to leave.
Added by Cullen X
As a result of losing his mate, Didyme, Marcus eventually became extremely apathetic. Marcus has never recovered from the loss of Didyme (unknowingly at the hands of Aro) and accounts for his apathetic and callous ways. He voted against destroying Renesmee in an 'almost bored fashion', not even looking at the Cullens and their allies while doing so. The others of the Volturi seem to recognize this aspect of himself, as none of the Volturi reacted at all to his vote. Marcus' personality is unknown prior to the death of Didyme, but he apparently loved her deeply. Ever since her death Marcus has sunk in to a extreme state of depression and apathy and is barely alive even by vampire standards. His state of mind seems to have been made worse by the fact that Aro had Chelsea force him to feel loyal to the Volturi and it has resulted in him being locked in a permanent state of grief-related apathy. During the meeting to discuss the Cullen situation in New Moon he barely acknowledges the proceedings and hardly speaks, just sits staring off in an almost bored manner. Despite this he does become animate in the presence of people with strong emotional ties like Bella and Edward and defends them on several occasions during encounters with the Volturi possibly because their love reminds him of the love he once had with Didyme.
- Main article: Relational empathy
Marcus has the ability to recognize relationships between people. When Marcus first encounters Bella and Edward, he is surprised by the intensity of their relationship. He shares this information mentally with Aro, by touching his palm.
Stephenie Meyer described Marcus's powers as the following: "Marcus's gift is actually quite valuable in the hands of someone who knows how to use it. For example, imagine Marcus on the battle field. He sees the binding ties between the enemy the guard faces. He can tell who the leader is just by watching the way the others are tied to him or her. He can see how to destroy the resistance simply by picking off a few key people. He doesn't just see romantic relationships, but also ties of family and friends, loyalty and devotion. He can tell if any given person would die for another. Off the field of battle (as the Volturi rarely leave their home), Marcus's gift is valuable politically (for lack of a better word). It's an amazing gift in a diplomatic situation. Plus, when you're sitting on an empire, it’s nice to be able to see when someone's loyalty starts wavering. Or if anyone is getting too fond of anyone else. Can you see the potential now? Marcus didn't get where he is with some fluff skill."