“In athletics it is the first time we have gold, so it’s a proud moment for me and my country,” the 23-year-old Chopra told reporters.
“In the qualification round I threw very well so I knew I could do better in the final. I didn’t know it would be gold but I am very happy,” he added.
His gold medal success completes a remarkable journey for Chopra that began when he decided to lose some weight.
“I come from a farming background,” explained Chopra. “I was overweight and wanted to do some fitness training.
“Somehow I ended up in an academy, and picked up javelin throw. The love affair started and now I’m here with this medal standing in front of you.”
The Czech Republic’s Jakub Vadlejch and Vitezslav Vesely won silver and bronze respectively.
India has now taken home seven medals in total at Tokyo 2020 — one gold, two silver and four bronze.
Priyanka Gandhi Vadra, general secretary of India’s opposition Indian National Congress party, congratulated Chopra on Twitter: “What an outstanding performance. History has been made. India is so proud of you.”