I did when boy. Only my witnessing was only aural listening to the radio. Little did I think that I would read of this 60th anniversary & new book.
‘Beyond’: UK author presents ‘exciting’ new book on Yuri Gagarin at Russian embassy in London, 60yrs since 1st manned space flight [rt.com]
I am too young, but I did witness the first moon landing and read about Yuri Gagarin with breathless wonder as a boy.
The shame being that in a plot worthy of a Dan Brown novel, once the USSR fell it was revealed Gagarin's achievement turned out to be possibly a propaganda exercise to cover the fact that Vladimir Ilyushin in the 'Rossiya' spacecraft was actually the first man to orbit earth in space but had died during his return to earth, five days before Vostok "1" was launched.
Ilyushin purportedly died in a car crash on the same day  Rossiya was tracked by French military radar returning to earth.
To this day Russia insist that Rossiya was unmanned and that the credit go to Gagarin, undoubtedly time will tell. 
 LenHazell53
                                                
                                                Level 9
                                                Apr 10, 2021
                                            
                                                
                                                    LenHazell53
                                                
                                                Level 9
                                                Apr 10, 2021                                            
                                        And if the yanks hadn't started the cold war there would have been no need for such doubt.
@altschmerz Interesting, seems the story keeps changing, seems now he did not die in 1961, but crashed in China, and spent some time there in a coma, but re-emerged some time later as the founder the Soviet Rugby Federation in 1967.
Still fascinating story nonetheless, thanks very much for the extra information.