Jerome was the youngest, least serious, and probably the least able of Napoleon's brothers, but this wouldn't have been a problem if his illustrious brother hadn’t insisted on appointing Jerome to posts that were beyond his abilities.
Jerome was born at Ajaccio on 15 November 1784. His father Carlo Maria Buonaparte died in 1785, so Jerome grew up without a father.
In 1793 the family was forced to flee from Corsica after they became associated with the pro-French faction. Jerome drifted for several years, and was poorly educated and already lazy. Despite this he was appointed to Napoleon's Consular Guard, but had to leave after a duel with Davout's brother.
In 1800 Napoleon got Jerome to join the Navy. Despite another unimpressive performance he was promoted to Admiral, but soon angered his brother after he left his ship to visit America, where he married Elizabeth Patterson, the daughter of a Baltimore millionaire. Napoleon refused to allow Elizabeth to enter his empire, and she was forced to settle at Camberwell where she gave birth to a son.
In 1805 Napoleon had the marriage annulled (widening a rift with the Pope, who refused to annul the marriage) and he forced his brother to marry Princess Frederica Catherina of Wurttemberg.
In 1806 Jerome left the fleet to command a Bavarian Division during the war against Austria. He was given a corps during the winter war against Russia in 1806-7, then after Eylau command of the French and allied armies in Silesia.
In December 1807, after the defeat of Prussia, Napoleon created the Kingdom of Westphalia. This was made up of Prussia west of the Elbe and some land from Prussia's allies, including Brunswick. The Kingdom of Westphalia was the largest of the many kingdoms Napoleon created, and became part of the Confederation of the Rhine, but despite its size Westphalia was an improvised kingdom.
Jerome was made King of Westphalia, a title he held until 1813. During his reign there was a great deal of reform in Westphalia, including the abolition of seigniorial dues, the formation of an indirectly elected legislature and the introduction of the Napoleonic Legal Code. Jerome wasn't involved in much of this activity and instead spent most of his time enjoying an extravagant lifestyle at his court at Kassel.
At the same time Napoleon was draining money and resources from the new kingdom, and Westphalian troops fought in Spain and took part in the Russian campaign of 1812. In 1809 Jerome commanded X Corps, but his performance was poor.
Despite his repeated failures Napoleon still insisted on appointing family members to key positions. At the start of the Russian campaign of 1812 Jerome was given command of the Second Supporting Army. This was a multinational force containing his own VIII Corps (18,000 men from Westphalia), General Poniatowski's V Corps (36,000 Poles), General Reynier's VII Corps (17,000 Saxons) and General Latour-Maubourg's IV Cavalry Corps (8,000 Poles, Westphalians and Saxons), for a total of 79,000 men.
Jerome's army was given a vital task at the start of the invasion. While Napoleon led the main army towards Barclay de Tolly's First Western Army (the northern of the two main Russian armies), Jerome was to advance east from Warsaw to prevent Prince Bagration from moving his Second Western Army north towards Barclay. Napoleon's original plan failed, mainly because the Russians retreated quicker than he had expected, but Jerome's progress was alarmingly slow, even at this early stage in the war.
At the end of June Napoleon adopted a new plan, with the aim of trapping and defeating Bagration's army. Once again Jerome had a key part to play in this plan, advancing east to press Bagration and stop him from retreated east. Once again Jerome moved slowly and failed to make contact with the Russians. He was also slow at reporting this news to Napoleon, who was furious and sent a stinging rebuke to his brother. The final blow came when Davout announced that he was taking command of all troops on the French right. Jerome resigned his command and on 14 July left the army to retreat to Westphalia.
During 1813 Jerome attempted to raise forces in Westphalia, but his subjects were now restless, hoping for the removal of the French dominance. Kassel was taken by the Russians in September. Although it was soon retaken Jerome's wife had already fled to Paris. In October Jerome followed her, again angering his brother. As Napoleon's Empire began to collapse Jerome's wife attempted to convince her father to intervene on Jerome's behalf. Her father insisted that she abandon Jerome's cause, and she refused, suggesting that the marriage was quite successful.
Jerome supported his brother during the Waterloo campaign, where he was given command of a division. His division fought well at Quatre Bras. At the start of the battle of Waterloo Jerome was sent to make a diversionary attack on the strong position at Hougoumont, but turned the diversion into a series of full scale attacks that failed to take the chateau. Napoleon failed to intervene to stop these attacks. For once Jerome demonstrated a great deal of determination, although sadly misdirected.
After the final fall of Napoleon Jerome threw himself of the mercy of his father in law, who kept him under semi-arrest for two years although he was given the title Count of Montfort in 1816.
After his release the couple lived in Trieste, then Rome, then Florence. Catherine died in Florence, and Jerome married again, this time to the Marchesa Giustina Bartolini, a wealthy widow.
In 1847 King Louis-Philippe gave Jerome permission to return to France. In the following year the king was overthrown and Louis-Napoleon (the future Emperor Napoleon III) came to power. Jerome's career now revived. He was made governor of Les Invalides, made a Marshal of France and served as President of the Senate.
Some of Jerome's children were more able than their father. His son with Elizabeth, Jerome, returned to the United States. His elder son served with the French Army in the Crimea, while his younger son served as Theodore Roosevelt's Navy Secretary in 1905-6 and as US Attorney General.
His surviving son from his second marriage, Napoleon Joseph Charles Paul Bonapart, became heir to the Bonaparte succession after the death of Napoleon III and his son the Prince Imperial.
Jerome was seen as good natured but lazy. Napoleon was often very harsh towards him, telling him in 1813 that him 'you are hateful to me. Your conduct disgusts me. I know no one so base, so stupid, so cowardly, you are destitute of virtue, talents and resources..', but the fault surely lies with Napoleon for appointing his brother to roles that were clearly beyond him.