[1] In 1800, he was promoted to colonel and appointed teniente del rey (equivalent to the British lord-lieutenant) for Santa Cruz de Tenerife.

The Junta Suprema de Sevilla later confirmed O'Donnell as the new commander general despite counter-accusations claiming that, in connivance with England, he had intended to declare the independence of the islands.

[2] Once his appointment was confirmed, in October 1808 he sent two Infantry battalions and two Artillery companies, plus numerous provisions, to mainland Spain.

[1] O'Donnell's request to be transferred to the mainland for active service in defending Spain was granted in June 1809.

The following August he handed over his command to Field Marshal Carlos Luján and left for Cádiz shortly thereafter.