The Vulcan salute came from a memory he was supposed to suppress. At age 8, his father told him not to look during a Jewish priestly blessing in a Boston synagogue. He looked. He put that gesture in Spock's hands, and it's now older than most of the people who flash it. He landed the role through a 1963 guest spot on Gene Roddenberry's The Lieutenant. NBC's marketing team tried to have Spock cut before broadcast, arguing the pointed ears would alarm Bible Belt viewers. They lost that argument. Spock outlasted everything NBC produced that decade.
The book that was supposed to separate him from Spock only fused them tighter. I Am Not Spock (1975) was widely read as rejection. Nimoy called naming it that 'a big mistake.' He fixed it with I Am Spock in 1995, whose foreword is written in Spock's own voice as a letter to Nimoy. The man who supposedly couldn't stand being Spock directed Three Men and a Baby in 1987, the highest-grossing film that year. His last public act was tweeting anti-smoking warnings after COPD caught up with him thirty years after he quit. He was useful until the end.
Before Spock, Nimoy was driving cabs and selling vacuum cleaners door to door. He reportedly gave JFK a ride once. During the Star Trek years he briefly ran a Canoga Park pet store called 'Leonard Nimoy's Pet Pad.' The Nerve Pinch was his idea, invented to keep Spock out of the fistfights that felt wrong for the character. He built more of the iconography than most people realize. The last five years of his life passed without a word to William Shatner, after Shatner secretly filmed him for a documentary without permission. Shatner missed the funeral and told press he felt 'really awful.' Filming someone without permission will do that.
His final tweet ('A life is like a garden... LLAP') was retweeted more than 120,000 times. President Obama issued a formal tribute noting 'Leonard was Spock.' Burial at Hillside Memorial Park on March 1 drew Zachary Quinto and J.J. Abrams. William Shatner missed the service and told press he felt 'really awful' about it. His son Adam Nimoy's documentary For the Love of Spock released in 2016.