Chicago was the setting for "No one who saw him can forget his personal appearance at that time. Tall, angular and awkward, he had on a short-waisted, thin swallow-tail coat, a short vest of the same material, thin pantaloons, scarcely coming to his ankles, a straw hat and a pair of brogans with woolen socks."
https://books.google.ie/books?id=SPEiBQAAQBAJ&pg=PA40 That was in 1847.
His first new suit apparently was bought in 1834 when he was elected to the legislature (in Vandalia, Illinois) "he had not a dollar. But here, again, his reputation was his capital. He went to a friend and said, " I want to make a decent appearance in the legislature. Lend me some money to buy some clothes, won't you? you know I'll pay you, some day."
Out of the two hundred dollars his friend had loaned him, he bought a suit of decent clothes. They were not elegant — not "purple and fine linen"; they were what w r as known as " blue jeans " — the workman's best dress of that simple and homely western country."
His first
legal suit was Hawthorn vs. Woodridge, in the Sangamon County Circuit Court. Not Chicago, and one wouldn't say a "new suit" in that context.