Henry VI, Part 1, often referred to as 1 Henry VI, is a history play by William Shakespeare—possibly in collaboration with Christopher Marlowe and Thomas Nashe—believed to have been written in 1591. It is set during the lifetime of King Henry VI of England. Whereas Henry VI, Part 2 deals with the King's inability to quell the bickering of his nobles and the inevitability of armed conflict and Henry VI, Part 3 deals with the horrors of that conflict, Henry VI, Part 1 deals with the loss of England's French territories and the political machinations leading up to the Wars of the Roses, as the English political system is torn apart by personal squabbles and petty jealousy. Although the Henry VI trilogy may not have been written in chronological order, the three plays are often grouped together with Richard III to form a tetralogy covering the entire Wars of the Roses saga, from the death of Henry V in 1422 to the rise to power of Henry VII in 1485. It was the success of this sequence of plays that firmly established Shakespeare's reputation as a playwright. Some regard Henry VI, Part 1 as the weakest of Shakespeare's plays. Along with Titus Andronicus, it is generally considered one of the strongest candidates for evidence that Shakespeare collaborated with other dramatists early in his career.