What happened, and when
The first spacewalk was made by the Soviet cosmonaut Alexei Leonov on 18 March 1965, during the Voskhod 2 mission. The first American spacewalk was made by Ed White on 3 June 1965, during Gemini 4. Neither of these took place in 1967. In fact, no spacewalks of any kind happened in 1967, because there were no crewed spaceflights by the United States that year, and the only Soviet crewed flight, Soyuz 1 in April, did not include one.
Leonov and Voskhod 2
Voskhod 2 carried two cosmonauts, Pavel Belyayev as commander and Leonov as the man who would leave the spacecraft. A flexible airlock was extended from the side of the capsule, and Leonov entered it and then moved out into space, attached to the spacecraft by a tether. He spent roughly ten to twelve minutes outside, although accounts give slightly different timings.
The event nearly went wrong. According to Leonov’s later descriptions, his suit stiffened and ballooned in the vacuum, which made it hard to bend and left him unable to re-enter the airlock in the normal way. He is reported to have reduced the pressure in his suit to make it flexible enough to get back in. Voskhod 2 then ran into further trouble, with a problem in the landing system that forced a manual re-entry and a landing far from the planned zone, in forest in the Urals. The crew survived, but it took time to reach them. The seriousness of these difficulties was not widely known outside the Soviet Union until years afterwards.
Ed White and Gemini 4
The American response came just under three months later. Ed White left the Gemini 4 capsule, with command pilot James McDivitt remaining inside, and spent about twenty minutes outside. White used a hand-held manoeuvring gun that released compressed gas, and he moved with more control than Leonov had. Accounts report that he was reluctant to come back in, and was called back by mission control. The two crewmen then closed the hatch, which proved difficult to lock, but the capsule returned safely.
The significance of White’s walk is that it was American, filmed and publicised, and that it demonstrated the potential for working outside a spacecraft. It also gave White, who would die less than two years later in the Apollo 1 fire, a place in popular memory.
Learning to work in space
Early spacewalks showed how hard it was to do useful work in vacuum. There was little to hold on to, and effort in a pressurised suit quickly led to overheating and fatigue. Later Gemini missions in 1966 tested ways of dealing with these problems. Some astronauts struggled with tasks outside. Edwin “Buzz” Aldrin, on Gemini 12 in November 1966, made a great improvement by using handholds, foot restraints and carefully rehearsed movements, including underwater practice, and he completed a series of tasks over several hours.
These lessons mattered because Apollo would need astronauts to work outside, first for transferring between spacecraft and then on the Moon. The Gemini programme ended in November 1966, and the Apollo programme was not yet flying crews.
Why 1967 had none
The reasons were practical. The Gemini programme was complete. The Apollo 1 fire in January 1967 halted American crewed flights until October 1968. The Soviet side attempted one crewed mission, Soyuz 1, in April 1967, which ended with the death of Vladimir Komarov when the parachute failed during landing. The Soviet programme paused its crewed flights for a long period afterwards, and the Voskhod programme had already ended in 1965.
The setbacks of that year are one reason the space race looks quiet in crewed terms in 1967, even though uncrewed work such as the Apollo 4 test continued.
What came next
The next spacewalk was in January 1969, when two Soviet cosmonauts, Yevgeny Khrunov and Alexei Yeliseyev, moved from Soyuz 5 to Soyuz 4 through open space after the two craft docked. Later in 1969 American astronauts tested Apollo equipment in Earth orbit before the first walk on the Moon in July 1969, which was a different kind of excursion, on a surface, but one that built on the earlier experience of working outside in a pressure suit.
Leonov went on to remain famous in the Soviet Union and later in Russia, and he also commanded the Soviet side of the Apollo-Soyuz mission in 1975.