Yes it was, history is very clear. We didn’t have an official border patrol until 1914. We didn’t pass any laws restricting immigration until the Page Act of 1875, the Chinese immigrants it concerned becoming the very first “illegal aliens”.
All Federal laws concerning itself with immigrants before then, from the 1870 law on back, dealt exclusively with naturalization. Not whether if immigrants could come here.
USCIS, the agency which manages our immigration today, describes 18th and 19th century immigration this way:
“***Americans encouraged relatively free and open immigration during the 18th and early 19th centuries, and rarely questioned that policy until the late 1800s. After certain states passed immigration laws following the Civil War, the Supreme Court in 1875 declared regulation of immigration a federal responsibility. Thus, as the number of immigrants rose in the 1880s and economic conditions in some areas worsened, Congress began to pass immigration legislation.***”
Ellis Island was opened as THE point of entry, in 1892.
Prior to that, States handled immigration screenings. It was more important at that time, legally, that a STATE accept the immigrant, than the distant Federal Government.
Likewise the Southwest border. Ever hear of the Texas Rangers? THEY patrolled the borders. The border with Mexico was ALWAYS a source of danger and intrigue.