Their story
(The surviving account on this page begins partway through the story.)
When the emperor Alexis lay dying, his wife, the empress-mother, tried to make him leave the throne to their son-in-law Bryennius instead of their son John; Alexis refused. Their daughter Anna Comnena even plotted against her brother, but Bryennius would not go along.
John slipped the imperial signet ring from his dying father's finger and had himself proclaimed before his mother and sister could act. Called John the Beautiful, he was praised for his character. His wife, the Empress Irene, was gentle, pious and charitable, known as "the Hospitable." She dressed plainly, more like a nun than an empress, amid a court given to luxury. She founded the monastery of the Saviour at Constantinople and died before her husband.
Alexis reproached his wife on his deathbed, saying he now had to attend to God alone, and she answered him scornfully. When Bryennius refused to join the plot, Anna said nature had mistaken the sexes. Alexis lived another twelve hours after John took the ring, but by then John had secured the throne. Irene's plain dress and meek spirit were held up as an example of moderation.