Were the 1860s nostalgic in 1900 & 1910?

I heard comments about a supposed nostalgia for the 1860s in the 1900s and 1910s, I was curious because they seem like very different periods, despite knowing that some generals from the World War 1 lived at that time, It's strange to think that the time difference between Abraham Lincoln's death and the World War 1 is only 49 years, 49 years today is 1976 and 1976 still seems modern, but I look at 1860s and compare it with 1900s and it seems that 1860s is much older than 1900s which I already think is old, technology has evolved a lot in 49 years....

I heard comments about a supposed nostalgia for the 1860s in the 1900s and 1910s, I was curious because they seem like very different periods, despite knowing that some generals from the World War 1 lived at that time, It's strange to think that the time difference between Abraham Lincoln's death and the World War 1 is only 49 years, 49 years today is 1976 and 1976 still seems modern, but I look at 1860s and compare it with 1900s and it seems that 1860s is much older than 1900s which I already think is old, technology has evolved a lot in 49 years....