Matthew Reginald Crawley was a character on the period drama, Downton Abbey. He was played for the series first three seasons by actor Dan Stevens.
The unknown heir presumptive
Matthew was the son of the late Reginald Crawley, a doctor, and his wife, Isobel Crawley Grey, a nurse. He was clever and smart and made a living as a solicitor in Manchester.
He was introduced as the next in line (after the deaths of James Crawley and his son, Patrick) in succession to inherit the estate of Downton, a small village located in the Northern Yorkshire region of England.
Upon hearing that he would become the new heir presumptive, he would move, along with his mother, to Downton, and take up residence in Crawley House. He would become a solicitor in the nearby town of Ripon to support his work.
He would first meet Lady Mary Crawley, when she rode up to Crawley House, and was at first repelled by his cockiness. They would eventually unbend towards one another and slowly fell in love.
During Sybil's season in London, Matthew had expected Mary to accept his proposal, but when she didn't, he took it back and left her. He would be called to war (he would be injured, and William Mason, his batman, would be injured and would later die of his injuries), and would become engaged to a solicitor's daughter, Lavinia Swire. Mary would be engaged to a scandal rag publisher named Sir Richard Carlile.
Matthew would overhear Sir Richard berate Mary. Although he wasn't engaged to her anymore, he was still protective of her, and he would later get into a fistfight with the nasty publisher. Infuriated, Matthew would hurl a vase at the contemptible man. He left in a huff, and Matthew sheepishly apologized for the vase being broken.
Violet reassured him that the vase was an ugly ornament that a despised great aunt had given her and her husband, and that she had hated the thing for over fifty years!
Out in the snow, outside of Downton, Matthew would again propose to Mary and this time, she would accept.
In the third season, they would be married, which meant that Matthew had to meet and be questioned by Mary's grandmamma, Martha Levinson. Matthew would also come to the aid of Sybil's husband, Tom Branson, after a cruel prank by a former suitor of hers named Larry Grey, the son of his mother's later husband, Lord Merton. He named Tom his best man.
The wedding went off without a hitch, but troubles would come into play when Lavinia's father named him as the beneficiary of his fortune. He would use said fortune to buy one half of Downton, making him co-master of the Estate.
Eventually Mary gave birth to their child, a son named George Crawley. Sadly, he would only lay eyes on him once, before he was killed in a car accident. Mary would be devastated and would be in mourning for six months.
He left a will naming his wife as the heiress of his estate. Although his father in-law, Robert Crawley, hoped against hope that it wasn't a will, it was declared that the paper was written with the intent of it to be considered a will until a proper will was written. As a result of this, Mary was named his heiress.
When Matthew died, his son George would become the new heir presumptive of Downton, as he was the next in line of succession. This would make mother and son co-heirs of Downton. Until he became of age, Mary would handle his affairs, as well as the affairs of her own shares of the estate. Barring any complications in which he could have died (either by natural causes or by World War II, which would occur when he came of age), George would become the eighth Earl of Grantham upon the death of his grandfather.