At 9 p.m. on Monday, January 4, 1802, Andrew Roberts explains (in Napoleon: A Life), Napoleon’s brother Louis was married to Josephine’s daughter Hortense by the mayor of Paris’ 1st arrondissement:
It was only one of a large number of marriages arranged by Napoleon, whose involvement in the nuptial lives of others was almost uniformly disastrous–certainly so in this case, as very soon Louis, who was in love with someone else at the time, could hardly bear to share a room with Hortense, and vice versa. Napoleon treated Hortense as his own daughter. Everyone liked her except the man Napoleon selected to marry her.
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Reviving the old royal practice by which generals and senior dignitaries had to ask the head of state’s permission to marry, Napoleon attempted to marry his generals into Ancien Régime families. The marriages that Napoleon opposed, such as Lucien’s and Jérôme’s (to his first wife), tended to be happier than the ones that he and Josephine matchmade.