The short answer: Web addresses are in English because the people who developed the standards for Web addresses were, for the most part, English-speaking Americans.
The longer answer: In the earliest days of the Internet, the only way to connect with a remote computer was to provide its unique IP address, a long string of digits such as But in 1983, as the number of computers on the network continued to grow, the University of Wisconsin developed the Domain Name System (DNS), which maps numeric IP addresses to more easily remembered domain names like

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