According to Official Guinness Records,
The first person to observe, measure and record the transit of the planet Venus across the Sun was Jeremiah Horrocks (UK) who monitored the event on 24 November 1639 from Lancashire, UK. The transit of 8 June 2004 was witnessed by millions of people worldwide
Horrocks, along with his friend William Crabtree (also UK), were probably the only two people in the world who witnessed this event. Transits of Venus across the face of the Sun are extremely rare due to the geometry of the orbits of the planets. Of the millions of people who witnessed the transit of 8 June 2004, none had seen the previous transit, which occurred in 1882.
For a complete list of 1639 records, please visit 1639 Guinness Records in United Kingdom.