In Our Image: America's Empire in the Philippines by Stanley Karnow is the essential starting point for understanding the country's modern history — the Spanish-American War, US colonial rule, the Commonwealth period, and the long aftermath. Karnow is thorough and readable.
Ghosts of Manila by James Hamilton-Paterson captures the chaos, violence, and hidden lives of Manila's underclass. It's fiction that reads like reportage, and it gets the city's contradictions right in a way that most travel writing does not.
The Blue Afternoon by William Boyd is a novel that moves between 1930s Hollywood and 1902 Manila. The Philippines sections are evocative and grounded, depicting the strange colonial moment when American and Spanish cultures were colliding on the islands.
God's Dust by Ian Buruma is a series of sharp, slightly melancholy essays on Southeast and East Asian national identity, with a chapter on the Philippines that cuts through the country's cultural confusion — Catholic yet Malay, Americanized yet fiercely particular — with unusual clarity.
Lieutenant Ramsey's War by Edwin Price Ramsey is a firsthand account of the guerrilla campaign against the Japanese occupation of the Philippines, told by an American cavalry officer who disappeared into the mountains and fought for three years. Vivid and underread.
Noli Me Tangere by José Rizal is the Filipino national novel, written in 1887 — a fierce satire of Spanish colonial society that helped ignite the independence movement. Rizal was executed by the Spanish at 35. Read it before you visit the country.
Culture Shock! Philippines by Alfredo and Grace Roces is a practical guide to Filipino customs and social norms: the logic of hiya (shame), pakikisama (group harmony), and utang na loob (debt of gratitude). Useful for anyone spending more than a week in the country.