Carlos Ghosn's push to make the relationship between Nissan and Renault stronger was undermined by Nissan executives and the Japanese Government, according to emails leaked to Bloomberg.
The emails reveal the Japanese Ministry of Economy, Trade and Industry was concerned merger plans would disproportionately benefit Renault and its largest shareholder, the French state.
They were sent directly to Ghosn or copied him in, and "show Nissan's leadership trying to protect the company's interests in a relationship the Japanese already saw as one-sided", according to the Bloomberg report.
Given the political nature of the relationship between Renault and Nissan, executives from the latter pushed hard to ensure Japanese government officials didn't damage things by over-reacting.
France was reportedly keen to make the two-decade long alliance permanent, something the Japanese Government and Nissan executives didn't appreciate.
Carlos Ghosn has maintained his innocence since being arrested, arguing the case against him is a conspiracy.
In a seven-minute video, the now-disgraced executive says people behind the coup were afraid about Nissan's autonomy as the Renault-Nissan-Mitsubishi Alliance became more closely aligned.
Although he pitched himself as "the fiercest defender of the autonomy of Nissan", the executive argued the company is underperforming at the moment, and the promise of autonomy is "based on performance".