simulative monetary policy to solve the recession. The fall of Keynesianism also credited to the fact that many economists did not take into account the probability of stagflation (Blinder, 2013). Historical data pointed out that high unemployment rates were related with low inflation rates and vice versa, as shown in the Phillips curve (Khan Academy, 2017). The theory was that a high demand for goods increased prices, which in turn stimulated companies to employ more people. Likewise, high employment rates augmented demand. During the 1970s stagflation, it became obvious that the link between inflation rates and employment levels was sometimes unstable. As a result, macroeconomists were unconvinced about Keynesianism, eventually steering to the end of the impact of Keynesian theories in economic strategies. Monetarist economists, such as Edmund Phelps and Milton Friedman clarified a shift in the Phillips curve: they maintained that when companies and workers anticipated high inflation, there was a shifting up of the Phillips curve, suggesting that high inflation can occur at any rate of unemployment (Khan Academy, 2017). Unambiguously, they argued that if inflation remained high for many years, workers and companies would begin emphasizing its consequences during wage negotiations, causing in a quick increase of earnings and firms’ prices, which further quickened inflation. This enlightenment was an extreme case of criticism of Keynesianism, and Keynesians progressively agreed the explanation. This reduced Keynesianism spread and influence on economic policies. To conclude, it is evident that the spread and impact of Keynesianism was largely accelerated by the unmatched economic success and constancy in the post-war period from 1945 until 1973. The basis of Keynesianism was government intervention using active monetary and fiscal actions to normalize aggregate volatility in market economies. Its collapse could have accredited to the 1970s stagflation depicted by an instantaneous increase in both unemployment and inflation rates. Critics maintain that stagflation was an unavoidable heritage of demand management policies associated with Keynesian economy. The critical fall of Keynesianism was noticed by the end of the neoclassical synthesis conventional position because of empirical and theoretical weaknesses. The fall of Keynesianism was also triggered by the fact that many economists of that time did not take into account the probability of stagflation.