Mongolian

Mongolian sits at the far end of the eastern road out of Aramaic. Aramaic passed to the Sogdian merchants of the Silk Road, Sogdian to the Uyghurs, and around 1204 the Mongols took the Uyghur alphabet for their own language. It is the same family of letters as the Aramaic plaque records — carried east, stage by stage, until it reached the tents of the Mongol state.

Somewhere on that journey the script was rotated. Aramaic was written right-to-left in horizontal lines, but Mongolian is written in vertical columns, top to bottom, the columns marching left to right — the same letters, turned ninety degrees. It is cursive, so letters connect and take different shapes at the start, middle and end of a word, much like Arabic.

The same letters as Aramaic — turned ninety degrees and stood on end.

In the 20th century Mongolia adopted a Cyrillic orthography for the Mongolian language, and the traditional vertical script is now strongest in Inner Mongolia — though Mongolia has legislated a return to it. The eastern branch is drawn out in the descent diagram: the Aramaic → Sogdian → Uyghur route connects this plaque to the Aramaic plaque. See the full tree in the Hall of Lineages.

These are four of the base letters. Each also has distinct initial, medial and final shapes chosen automatically when it joins its neighbours, and reading runs downward — the eye travels top to bottom, then left to the next column.