This section is from the book "The Law Of Contracts", by William Herbert Page. Also available from Amazon: Commercial Contracts: A Practical Guide to Deals, Contracts, Agreements and Promises.
At the outset the king's courts had no procedure and no machinery for enforcing executory contracts. In their earliest procedure a specific question was submitted to an assize, which they were required to answer. With the development of the jury, a greater freedom in forming the issue was permitted; but as long as no rules on the subject of measure of damages existed, there was no means by which the king's courts could enforce executory contracts except by specific performance. At an early period before the differentiation between law and equity, it seems as though the power of specific performance might have been exercised. With the growing rigidity of the common law, this power was abandoned. The result was that the king's courts had no available machinery for enforcing executory contracts, and this lack of definite rules on the subject of the measure of damages had its effect upon the theory of the relation of the different covenants in executory contracts, even after the king's courts finally began to enforce them. Until a definite set of rules on the subject of the measure of damages could be evolved, it was necessary to treat the different covenants on each side as independent and to allow each to recover against the other. The results thus reached were substantially the same as those reached under our theory of the measure of damages for breach of contract. Debt was of such antiquity, that it was tried by compurgation.1
2 Barbour, History of Contract in Early English Equity, IV Oxford Studies, 1 et seq. (73 et seq., 160 et seq.); Some Aspects of Fifteenth-Century Chancery, by Willard Barbour, 31 Harvard Law Review, 834; Early English Equity, by Oliver Wendell Holmes, 1 Law Quarterly Review, 162; 2 Essays in Anglo-American Legal History, 705. See also, The Origin of English Equity, by George Burton Adams, 16 Columbia Law Review, 87; Continuity of English Equity, by George B. Adams, 26 Yale Law Journal, 550; Early History of English Equity, by H. D. Hazel tine; Essays in Legal History, 261 (269);
Confusion of Law and Equity, by Henry H. Ingersoll, 21 Yale Law Journal, 58. See 10 Selden Society (Select Cases in Chancery), for contract cases, among them, that on p. 141.
The early reports of chancery cases assume the validity and enforceability of contracts, but at a period much later than the one under discussion. See Toth. 162 to 164, including cases in the reigns of Elizabeth and James I.
Some of the other courts possessed machinery by which they could compel the performance of a contract in some fashion. By its writ of subpoena and by its power to punish for contempt, equity had the means of enforcing performance of such contracts as it chose to perform. In addition to this it exercised a power to award damages for breach of contract where such relief was proper and where the case was one of which the king's courts would not take jurisdiction. The courts of the trading towns seem to have exercised a similar jurisdiction to award damages. The manorial courts had power to distrain the property of the debtor or promisor and to coerce him into performing his contracts.