Jacob Riis (1849–1914) was a Danish immigrant and photojournalist best known for his first book, How the Other Half Lives: Studies among the Tenements of New York. Published in 1890, the book shocked the conscience of Americans by showing in vivid detail the slum conditions of the Lower East Side of Manhattan, where Jewish, Bohemian, German, Italian, Chinese, and Irish immigrants were packed into tenements, many of them with no windows or ventilation, and waged a daily battle against overcrowding, crime, disease, filth, and poverty.