Robert Walker (after) ( 1607 - 1658 ) was a painter. Robert Walker (after) s works have been put up for auction numerous times, with realized prices surpassing estimated prices, varying from 636.84 USD for Portrait of a young gentleman, traditionally identified as General Jon Lambert, quarter-length, in a white collar and armour, in in 2005 to 6636.31 USD for PORTRAIT OF OLIVER CROMWELL (1599-16