Jacoba or Jacqueline of Wittelsbach (1401 – 1436) was Countess of Hainaut and Holland from 1417 to 1432. She was the only daughter of William VI, Count of Hainaut and Holland . Jacqueline was the last ruler of independent Hainaut and Holland. Following her death, the estates were incorporated in the control of the duchy of Burgundy.

As a child Jacqueline was married to John of Valois, Duke of Touraine and second son of Charles VI of France, who on the death of his elder brother Louis became dauphin. John of Touraine died in April 1417, and two months afterwards Jacqueline lost her father. Acknowledged as sovereign in Holland and Hainaut, Jacqueline was opposed by her uncle John of Bavaria, bishop of Liege. She had the support of the Hook faction in Holland. In 1418, her uncle and guardian John the Fearless, duke of Burgundy, organized her marriage to her cousin John IV, Duke of Brabant . By the mediation of John the Fearless, a treaty of partition was concluded in 1419 between Jacqueline and John of Bavaria; but it was merely a truce, and the contest between uncle and niece soon began again and continued with varying success.

In 1420 Jacqueline fled to England. There, declaring that her marriage with John of Brabant was illegal, she married with Humphrey, Duke of Gloucester (son of Henry IV of England) in 1422. Two years later Jacqueline and Humphrey, invaded Holland, where she was now opposed by her former husband, John of Brabant, after John of Bavaria having poisoned. In 1425 Humphrey deserted his wife, who found herself obliged to seek refuge with her cousin, Philip III, Duke of Burgundy, to whom she had to submit, and she was imprisoned in the castle of Ghent. John of Brabant now mortgaged the two counties of Holland and Zeeland to Philip, who assumed their protectorate. Jacqueline, however, escaped from prison in disguise, and for three years struggled gallantly to maintain herself in Holland against the united efforts of Philip of Burgundy and John of Brabant, and met at first with success. The death of John of Brabant (April 1427) freed the countess from her quondam husband; but nevertheless Pope Martin V pronounced Jacqueline's marriage with Humphrey illegal, and Philip, putting out his full strength, broke down all opposition. By a treaty, made in July 1428, Jacqueline was left nominally countess, but Philip was to administer the government of Holland, Zeeland and Hainaut, and was declared heir in case Jacqueline should die without children.

Two years later Philip mortgaged Holland and Zeeland to the Borselen family, of which Francis, lord of Borselen, was the head. Jacqueline now made her last effort. In 1432 she secretly married Francis of Borselen, and endeavoured to foment a rising in Holland against the Burgundian rule. Philip invaded the country, however, and threw Borselen into prison. Only on condition that Jacqueline abdicated her estates in his favour would he allow her liberty and recognize her marriage with Borselen. She submitted in April 1432, retained her title of duchess in Bavaria, and lived on her husband's estates in retirement. Jacqueline was killed in Teilingen Castle in 1436, and since she had no children, Philip of Burgundy inherited Hainaut and Holland.