Louis Alphonse Daniel Nicolas (1864–1939)—better known by his pen name A. L. M. Nicolas—was a Persian-born French historian and scholar of Oriental studies who is best known today for his early work on Shaykhism and Bábism.

[citation needed] Although primarily remembered for his academic contributions, Nicolas worked as an interpreter and diplomat with the French Consular Service in Persia for most of his life.

Nicolas was among the first Western orientalist to devote substantial attention to the life and teachings of the revolutionary Persian religious figure known as the Báb, and his work continues to serve as an important source for the study of the early history of Shaykhism, Bábism and the Baháʼí Faith.

I admit that during the two or three years of my study [of that book] I was often dazzled by the explanations that the Báb gives us for certain mysteries such as death, the resurrection, the Sirát – this bridge that passes over hell, narrow as a hair, sharp as a razor, and which the believer traverses with the rapidity of lightning.

The more I plunged into these meditations the more I admired the exalted genius of the one who, born in Shíráz, dreamed of uplifting the Muslim world; and [his] explanation of the meaning of the language of Shí'í belief impelled me gradually to write "Seyyed Ali Mohammed dit le Báb".