A treaty finalized by the UK may bring about the end of the .io domain. Last week, the British government announced that it has agreed to give up ownership of the Chagos Islands, a territory in the Indian Ocean it has controlled since 1814 — relinquishing the .io domain with it.

But first, let’s take a step back (and I mean far back) to see how we got here. According to the Encyclopedia Britannica, the Chagos Islands were settled by the French in the 1700s, who brought slaves to the archipelago. In 1814, the French ceded control of the Chagos Islands and the island country of Mauritius to the British. When the British took over, the Chagos Islands remained a dependency of Mauritius.

In 1965, the UK granted Mauritius its sovereignty, but the government decided to split off the Chagos Islands, making it a British Indian Ocean Territory. The UK ended up forcibly removing the Chagossian people so the US could build a military base on one of the islands, displacing more than 1,500 people, as detailed in this report from Human Rights Watch.

Eventually, the Chagos Islands — or the British Indian Ocean Territory — were given the IO country code. It was also assigned a matching .io country code domain in 1997. The British government granted the rights to sell .io domains to the Internet Computer Bureau (ICB), according to a 2014 report from GigaOm.

A country’s government is typically supposed to receive revenue for any sites that register using their country code domain. For example, Anguilla, which has the country code AI, was projected to make between $25 million and $30 million last year from websites registering with the .ai domain.

You’d think the Chagos Islands would make similar amounts of money from the .io domain. After all, thousands of buzzy tech startups and cryptocurrency companies — like itch.io, greenhouse.io, and opensea.io — adopted the domain, since “io” also serves as an abbreviation for “input/output.”

However, entrepreneur Paul Kane, who previously ran the ICB, told GigaOm that the British government collected some of the revenue, which came as a surprise to the Chagossian people. In 2020, the Chagossians submitted a claim to gain ownership of what they said was a $50 million property, as reported by Fortune.

But now, the UK’s finalized agreement will make the Chagos Islands part of Mauritius — a move Chagossians say the government didn’t even consult them on. With this change, the British Indian Ocean Territory is no more, calling into question the future of the .io domain.

As pointed out by the Every newsletter, the Internet Assigned Numbers Authority (IANA) has a process for retiring old country code domains within five years (with the possibility for extensions). The IANA established this rule after the Soviet Union’s .su domain lingered after its collapse, becoming a domain commonly used among cybercriminals.

Since then, IANA has also had to retire the .yu domain previously used for Yugoslavia, but it remained operational for years following the country’s breakup while government websites transitioned to new domains. And while the independent Solomon Islands does have the domain name .sb, where “B” stands for how it used to be a British protectorate, that domain was registered decades after it achieved independence. The UK still has the inactive .gb domain as well, but it’s considering getting rid of it.

For now, it’s still too early to tell what will become of the .io domain — whether it will go through a similar transitional period like .yu, or if the IANA will just let the Chagossans keep it. The Verge reached out to Identity Digital — the domain registrar that previously obtained the rights to sell .io domains — and IANA for information about .io’s future. We didn’t immediately hear back.