January 30, 1968

Tet Offensive

Tet Offensive begins with premature attacks in central South Vietnam

A calendar discrepancy sent part of the offensive forward a day early — and warned the defenders before the main assault reached Saigon and Huế.

12:35 a.m. at Nha Trang

Shortly after midnight on 30 January 1968, People's Army of Vietnam and Viet Cong units attacked cities and allied installations across southern I Corps and II Corps. The U.S. Army history counts eight major cities struck in this wave.

The first attack in that account began at 12:35 a.m., with mortar rounds landing near the South Vietnamese Navy Training Center at Nha Trang. Ban Me Thuot, Kontum, Pleiku, Qui Nhon, Da Nang, Hoi An and Tuy Hoa were also hit.

A day early, by mistake

Communist commanders had planned a coordinated offensive around the Tet holiday. A mix-up involving orders and the differing northern and southern lunar calendars sent units in parts of central South Vietnam forward about a day ahead of the main wave.

The precise reason is still debated; the calendar-and-orders mismatch is well supported, and declassified NSA history discusses alternative readings. Sources also count the 30 January targets differently, usually eight or nine, depending on how towns and installations are grouped.

What the early wave bought the defenders

General William Westmoreland recognized what the attacks signified, put U.S. commands throughout South Vietnam on full alert, and advised the South Vietnamese military to recall troops on Tet leave. The cease-fire was canceled.

The exposure was partial: the first day revealed the offensive but not its scale. In the early hours of 31 January the main wave struck 36 of 44 provincial capitals, 64 of 242 district towns and 5 of 6 autonomous cities, including Saigon and Huế.

Sources

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What the sources leave uncertain

The offensive is commonly dated 31 January because that was the main nationwide wave and the date of the attacks on Saigon and Huế. Declassified and official histories nevertheless document the opening attacks shortly after midnight on 30 January.
Sources count the 30 January targets differently—usually eight or nine—depending on whether smaller towns, installations or paired urban areas are counted separately.
The precise reason for the early attacks remains debated. A calendar/order mismatch is well supported, but declassified NSA history discusses alternative interpretations.