Legend has it that the term “block” plane comes from its use resurfacing butcher blocks, which are end-grained (or at least the good ones are). However it may also have been because of the block-like nature of the wooden mitre planes which were a precursor to the modern block plane.
The Dictionary of Tools describes a block plane as:
“…a range of metal planes about 3-7 in long with a variety of devices for holding the iron and adjusting the cut or mouth.“
As to their purpose, it goes on to say:
“These planes are designed for use with one hand for trimming small work. The low-pitch iron is especially suitable for end grain.“
Why metal planes, were there not wooden block planes? As it turns out, very few. This may be in part because of the deteriorative nature of wood, but also due to the smaller size of these planes – it may be that few survived from earlier periods. Most early block planes (pre-1800), were actually made of iron. A “shoe-shaped” Vergatthobel made of iron, and 4 inches in length is described in “A History of Woodworking Tools” (Goodman) from the 16th century. Goodman also describes an iron block plane from circa 1570 (Historical Museum, Dresden) – a small iron block plane, with the ends bent around in a semi-circular fashion. The interesting thing is that the blade is secured with a small thumbscrew threaded through a bar across the mouth. I suspect these planes were made of metal due to their small size, and conversely metal was only used in small planes due to the difficulty in construction and the cost involved.
With respect to all-wooden block planes, one of interest is the Novaya Zemlya plane (or Nova Zembla in Dutch). In 1596 a Dutch expedition sailed for China via the North-east Passage. The expedition was wrecked near the Novaya Zemlya archipelago, in Russia, and had to over-winter on the ice. Some of the stores they left behind, including this plane, a hand drill and chisel were found in the early 1870s. The plane is made of beech, is 6¾” in length, and 2½ wide, with the blade set at 45°. But was it a true block plane?
Smaller wooden planes did of course exist, in the guise of carriage-makers, or piano-makers planes, up to 7 inches in length, however these rarely fit the overall characteristics of block planes. Sometimes they were merely specialized smoothing planes – termed “smooth plane for end grain”, (or RABOT pour le bois debout in French).
Apart from these few specimens, there is little to say about pre-1800 block planes. Wooden planes that do feature more prominently are mitre planes – a descendant of the medieval block plane, the metal variants of these planes were the starting point for the design of English metal planes. The mitre plane is used mostly for shooting mitres, and performs particularly well on end grain. These mitre planes had the low-set blade, characteristic of block planes. There were of course wooden mitre planes, but these usually were much longer than their metal counterparts – up to 12 inches.
The first “block” plane offered by Stanley, the No.9 in 1870, was a mitre-plane. It had a “block” shaped body with a sole that had semi-circular ends, and a blade bedded at 20°, similar in style to the mitre plane shown below.
In great Britain, early block planes may have gone by another name – the Chariot plane. These planes were 3-5″ in length, and used in end-grain and cross-grain work, and were named because of their appearance.
It is hard to fathom why the block plane went from apparent obscurity to having its own category, with plane manufacturers from the late 19th century onwards to about 1950 producing copious forms of block plane with different blade adjustment (lateral and depth) mechanisms, as well as varied means of holding the blades in the plane, mouth adjustment mechanisms, and construction methods. It could be partly attributed to the cabinet-makers increasing need to build and fit cabinets onsite, making the use of a plane which could be carried in their apron highly beneficial.
Next – The evolution of the modern block plane.
working by hand 
I’ve just read your article on block planes, so I regret this comment is some years late! You say that legend has it that block planes were so called because they were used for planing butchers blocks. However, think it much more likely they were originally intended for planing engraving blocks.
Before the invention of photographic printing processes in the late 19th century, for an illustration to be reproduced in a book or newspaper it first had to be engraved on a block of end-grain hardwood, boxwood being the best. Making engraving blocks was therefore an important trade in the 19th century.
For a block to print properly, not only did the top surface have to be made perfectly flat and smooth, the thickness of the block had to match exactly that of the type into which it was set, i.e. the diameter of an old shilling, just under an inch.
There must have always been small planes for planing end-grain, but they don’t seem to have been called block planes before Stanley and other firms brought out their iron-bodied ones in the 1880’s (?). If my theory is right, it’s a bit ironic that only a few years after the modern block planes were produced the whole business of commercial engraving became obsolete, yet the name continues to the present day. Wood engraving only continued with artists who engraved and printed their own blocks by hand, and for certain special purposes for example tool catalogues, where if it was desired to illustrate a particular feature of a tool or machine it could be done more clearly by an engraving than in a photograph.
I make my own engraving blocks in an amateur way, and whilst the thicknessing can be done with a power router, I still use a block plane (Veritas, excellent) before the final stage of sanding.
Best wishes.