Tom Wroblewski, president of the Seattle machinists union that engaged in a bitter contract fight with aerospace manufacturer Boeing in recent months, has announced his retirement. The announcement adds a post script to a high stakes drama that had his union local not only fighting with management but with its own national leadership.

Wroblewski, president of International Association of Machinists and Aerospace Workers District 751, made the announcement Wednesday, citing health reasons. According to the Seattle Times, he has been hospitalized twice since Dec. 27 for ulcers.