He served with distinction during the First World War, first as a gunnnery officer on HMS Lion, and latterly in command of HMS Cambrian.
In November 1916, Heaton-Ellis was appointed chief of staff to Rear-Admiral Sir William Pakenham, commanding the Battlecruiser Squadron, in HMS Lion.
The Lion King | The Lion, the Witch and the Wardrobe | Lion | HMS Beagle | The Chronicles of Narnia: The Lion, the Witch and the Wardrobe | The Wind and the Lion | lion | HMS Victory | The Lion King (musical) | Lion Red Cup | HMS M31 | HMS Bounty | Golden Lion | HMS M23 | HMS ''Humber'' | HMS ''Bounty'' | The Lion in Winter | HMS M27 | HMS M25 | HMS Investigator | Henry the Lion | HMS M33 | HMS ''Beagle'' | Food Lion | Napier Lion | HMS Plumper (1848) | HMS Endeavour | The Lion Sleeps Tonight | sea lion | Old Red Lion Theatre |