For the last ten years, I have been engaged in looking at Chinese language documents from the 1960s Cultural Revolution in the Inner Mongolian area of China. It seems odd, describing to others why, for a lot of my leisure time, I've been poring over material which is almost devoid of literary merit - polemics against local leaders, attack documents, news-sheets produced by small Red Guard groups setting out ardent adoration of Chairman Mao, or abstruse ideological points within a debate, the main objectives of which hardly make sense to the Chinese themselves.

But these documents are one of the few windows onto a special, and very little known period in contemporary history. Visitors to the Inner Mongolian region now will find no memorials to this period there. They will find nothing about it in the museum which stands in the main square of the provincial capital Hohhot. Nor, for that matter, will they find many books about it in the local bookshops or the public library, standing just across the road from the province's university. The grand project of modernising China, which has engulfed Inner Mongolia like other regions in the country for the last two decades, has effectively swept away even most of the buildings and the material environment within which the great purges of the late 1960s occurred. The period isn't even accessible through human memory, because people are reluctant to speak openly about such a sensitive period.

The pamphlets, news-sheets and ...