His ancestors had often taken money, but had never borrowed it, and the Duke chafed under the necessity.

There was something about the process that went against the grain.

To sit down in pleasant converse with a man, perhaps almost a gentleman, and then lead up to the subject and take his money from him, seemed to the Duke's mind essentially low.

He could have understood knocking a man over the head with a fire shovel and taking his money, but not borrowing it.
So the Duke had come to America, where borrowing is notoriously easy.
Any member of the Mausoleum Club, for instance, would borrow fifty cents to buy a cigar, or fifty thousand dollars to buy a house, or five millions to buy a railroad with complete indifference, and pay it back, too, if he could, and think nothing of it.

In fact, ever so many of the Duke's friends were known to have borrowed money in America with magical ease, pledging for it their seats or their pictures, or one of their daughters--anything.
So the Duke knew it must be easy.