* Ancient times: Straw was a common material used for building roofs and other structures, particularly in rural areas. The weight of the straw was significant, and adding too much straw to the structure could cause it to collapse.
* The "last straw": The phrase refers to the final straw added to a pile that causes it to break, symbolizing the point where a person's patience or tolerance reaches its limit.
* Early usage: The phrase was first used in the late 16th century, with the first known printed example appearing in 1598.
Therefore, the phrase "last straw" originates from the literal act of adding too much straw to a structure, causing it to break. It has been used figuratively to describe the breaking point of patience or tolerance for centuries.