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We study the naked-eye observability of microlensing events for both known stars and possible massive compact halo objects (MACHOs). We nd that if both the dark matter disc and halo are composed of MACHOs in the Jupiter-mass range, microlensing events of naked-eye stars, undergoing at least one magnitude of magni cation occur at the rate of 1 per 2400 years, and have durations of from hours to days; we may thus surmise that the chance of at least one event occurring in the era of recorded history (the last 5,000 years) would be 1 ? e ?2:1 88%. For magni cation by known stars, we expect events at the rate of one per 40,000 years, so we should not be surprised not to have witnessed an event in the last 5000 years. However, in the last 200,000 years, while humans have inhabited the Earth, we expect of order 5 events, and thus a 99% chance that at least one observable event has occurred.

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