At first glance, sixteenth-century Cologne appears the perfect image of the post-Reformation confessionalized city. However, this public persona was just that – a convenient façade that disguised a consistent preference for accommodation over conflict. Though Cologne's leaders strove to project a fierce and steadfast dedication to Catholicism, the everyday experience of life in the Rhenish metropolis often defied such pretenses. Due to a combination of economic pragmatism, commitment to civic peace, and caution in an unpredictable environment, the ruling council consistently chose to turn a blind eye towards most non-Catholics in the city so long as they submitted to the public Catholic order. Cologne thus became a place in which Catholics and Protestants could live together in a shared community despite the authorities' outspoken rejection of religious pluralism. This dissertation explores how this compromise functioned, what pressures led to its eventual collapse in the early seventeenth century, and what lessons it imparts about the larger history of religious coexistence.