During the mid-1800s, missionary groups kept coming to the islands. Some of the missionaries later bought land; others were given land and houses in return for their services to the mō‘ī or the ali‘i nui. By this time, of course, traditional Hawaiian homes were being replaced by houses of stone and lumber. In central Honolulu, grass houses and small wooden buildings had given way to stores, hotels, public buildings, schools, and churches. After the Catholic mission returned to Hawai‘i and was welcomed this time, a Catholic school was built to train Catholic teachers. A group of Mormons who traveled to the West during the California Gold Rush also came to Hawai‘i to create a Mormon mission.
The whaling industry had caused first Lahaina on Maui and then Honolulu on O‘ahu to grow. Harbors on the other islands were now also crowded with whaling ships during the fall and spring months. It was said that one could almost walk from one end of Honolulu Harbor to the other on the decks of the whaling ships because they were packed so closely.
Honolulu soon became the business capital of the Pacific. Merchant ships brought cargoes from America, Europe, and China. Some of the goods were sold to other islands of the Pacific and far-off California. In 1820, Honolulu had been a village of about three to four thousand people. Twenty years later, there were twice that many people.
However, at the same time that newcomers were sailing to Hawai‘i and causing the overall population of the islands to increase, Native Hawaiians were dying in large numbers due to disease. Of an estimated Native Hawaiian population of 400,000 to 800,000 people before Western contact, in 1822 there were 200,000 Native Hawaiians, in 1836 there were 108,000, and in 1878 there would be only 48,000 Native Hawaiian people.