In theory, anyone born in lands ruled by the king was a citizen and anyone born elsewhere was an ‘alien’ or foreigner. However, this was often complicated.

• During the Middle Ages, England took control of Wales and officially it was in the king’s realm, but many Welsh people did not accept English rule.
• English armies invaded Ireland and controlled part of the country, but Irish people living under English rule were not treated as citizens because they were regarded as colonised people.
• During the Hundred Years' War between England and France, several parts of France changed hands. For example, Gascons from south west France were treated as English citizens until France took control of Gascony when they became ‘aliens’.
• Aliens could ask for letters of denization from the king which granted many of the rights of a citizen, such as the right to hold land. However this was only really available to people of higher status.
• The children of foreign-born residents were no longer classed as aliens if they were born in England.