I HOPE the reader will not think I have trespassed on his patience in introducing myself to him with some account of the manners and customs of my country. They had been implanted in me with great care, and made an impression on my mind which time could not erase, and which all the adversity and variety of fortune I have since experienced served only to rivet and record: for, whether the love of one’s country be real or imaginary, or a lesson of reason, or an instinct of nature, I still look back with pleasure on the first scenes of my life, though that pleasure has been for the most part mingled with sorrow.
It starts with the introduction, and he doesn't want to bore the reader. He wants to talk about the importance of sharing the customs and share how deep it is. He wants to talk about the customs regardless of everything he went through.