Explain the events that led up to the landmark case plessy vs. ferguson and why it was a landmark case?

The plaintiff in the case, was seven-eighths white and one-eighth black, and had the appearance of a white man. On June 7, 1892, he purchased a first-class ticket for a trip between New Orleans and Covington, La., and took possession of a vacant seat in a white-only car. Duly arrested and imprisoned, Plessy was brought to trial in a New Orleans court and convicted of violating the 1890 law. He then filed a petition against the judge in that trial, Hon. John H. Ferguson, at the Louisiana Supreme Court, arguing that the segregation law violated the Equal Protection Clause of the Fourteenth Amendment, which forbids states from denying "to any person within their jurisdiction the equal protection of the laws," as well as the Thirteenth Amendment, which banned slavery. 

The answer is on suffrage experience.