In 1798, Hompesch was warned that the French fleet that was sailing to Egypt under Napoleon Bonaparte intended to attack Malta as well.
He disregarded the warning and took no action to reinforce the island's defenses.
On 6 June 1798, the advance squadron of the French fleet reached Malta.
One ship was permitted to enter the harbour for repairs.
On 9 June the main fleet arrived.
The French commander Napoleon had a force of 29,000 men against Hompesch's 7,000.
Bonaparte demanded free entrance to the harbour for the entire fleet with the rationale being to gain water provisions.
Hompesch replied that only two ships at a time could do so.
Napoleon saw it as a provocation and ordered the invasion of the Maltese Islands.

On 10 June, the French fleet began disembarking.
The French forces were supported by a local insurrection of Maltese, many of whom wished to get rid of the Knights.
The rules of the Order prohibited fighting against fellow Christians and many of the French members of the Order did not want to fight against the French forces.
Hompesch capitulated on 11 June.
The following day a treaty was signed by which the Order handed over sovereignty of the island of Malta to the government of the French Directory.
In return, the French Republic agreed to "employ all its credit at the Congress of Rastatt to procure a principality for the Grand Master, equivalent to the one he gives up".
Hompesch was also promised an annual pension.
In 1798, Hompesch was warned that the French fleet that was sailing to Egypt under Napoleon Bonaparte intended to attack Malta as well. He disregarded the warning and took no action to reinforce the island's defenses. On 6 June 1798, the advance squadron of the French fleet reached Malta. One ship was permitted to enter the harbour for repairs. On 9 June the main fleet arrived. The French commander Napoleon had a force of 29,000 men against Hompesch's 7,000. Bonaparte demanded free entrance to the harbour for the entire fleet with the rationale being to gain water provisions. Hompesch replied that only two ships at a time could do so. Napoleon saw it as a provocation and ordered the invasion of the Maltese Islands.
On 10 June, the French fleet began disembarking. The French forces were supported by a local insurrection of Maltese, many of whom wished to get rid of the Knights. The rules of the Order prohibited fighting against fellow Christians and many of the French members of the Order did not want to fight against the French forces. Hompesch capitulated on 11 June. The following day a treaty was signed by which the Order handed over sovereignty of the island of Malta to the government of the French Directory. In return, the French Republic agreed to "employ all its credit at the Congress of Rastatt to procure a principality for the Grand Master, equivalent to the one he gives up". Hompesch was also promised an annual pension.
Ferdinand von Hompesch zu Bolheim