Ingelger or Ingelgarius (died 888) was a Frankish nobleman, who was the founder of the County of Anjou and of the original House of Anjou. Later generations of his family believed he was the son of Tertullus (Tertulle) and Petronilla.
Around 877 he inherited his father Tertullus's lands in accordance with the Capitulary of Quierzy which Charles the Bald had issued. His father's holdings from the king included Château-Landon in beneficium, and he was a casatus in the Gâtinais and Francia. Contemporary records refer to Ingelger as a miles optimus, a great military man.
Later family tradition makes his mother a relative of Hugh the Abbot, an influential counselor of both Louis II and Louis III of France, from whom he received preferment. By Louis II Ingelger was appointed viscount of Orléans, which city was under the rule of its bishops at the time. At Orléans Ingelger made a matrimonial alliance with one of the leading families of Neustria, the lords of Amboise. He married Adelais, whose maternal uncles were Adalard, Archbishop of Tours, and Raino, Bishop of Angers. Later Ingelger was appointed prefect (military commander) at Tours, then ruled by Adalard.
At some point Ingelger was appointed Count of Anjou, at a time when the county stretched only as far west as the Mayenne River. Later sources credit his appointment to his defence of the region from Vikings, but modern scholars have been more likely to see it as a result of his wife's influential relatives. He was buried in the church of Saint-Martin at Châteauneuf-sur-Sarthe. He was succeeded by his son Fulk the Red.
His wife was Adelais. Her good connections may have helped her husband gain the title of Count of Anjou.